The check engine light is a warning that the car’s computer found a problem. It usually means there’s a code stored that a mechanic can read to find the cause.
Traction control helps the car grip the road. If the traction control warning lights come on, it can mean the system isn’t working correctly or the car detected a problem.
A fault code is like the car’s way of leaving a clue for the mechanic. It tells you what kind of problem the computer noticed so you can track it down faster.
P0456 is a computer code that usually means there’s a small leak related to the car’s fuel-vapor emissions system. It’s the kind of code that can be caused by a loose cap, a cracked hose, or a leaking EVAP part.
The charcoal canister is a part that traps fuel vapors so they don’t escape into the air. If the car thinks there’s a small EVAP leak, mechanics often check the canister and the hoses around it.
The vent valve is a small control valve that helps the car manage fuel vapors. If it’s not working, the canister can’t “breathe” correctly, and the emissions system won’t function as intended.
Heat shields are protective metal panels that keep other parts from getting too hot from the exhaust. If they’re rusted in place, you may have to remove exhaust parts just to get to the job.
The exhaust system carries the engine’s fumes out of the car. In this situation, it blocks access to the emissions canister, so the mechanic may need to move or remove parts of the exhaust to reach it.
The host mentions New Jersey because the car inspection rules there affect what gets checked. If the problem doesn’t trigger a warning code during the test, the car may still pass.
Your car has a computer that checks emissions and sensors. A drive cycle is a particular kind of driving that helps the computer finish its tests. If the tests run and no warning codes come back, the problem may be intermittent.
Monitors are the car’s built-in “checklist” tests. They only finish after the right kind of driving. If the monitors don’t run, you might not get a clear answer on whether the problem is truly gone.
An intermittent failure is a problem that comes and goes. The car might not show any warning codes during testing, but the issue can return later. That makes it harder to diagnose because it’s not present all the time.
Term
mechanics obligation
“Mechanic’s obligation” here is the idea that a shop should do more than just pass/fail a scan—it should guide the customer based on diagnostic findings, especially when failures are intermittent and may not set codes during inspection. It frames the responsibility as advising next steps rather than ignoring the risk.
Four wheel alignment means adjusting how all four tires sit and point. If the angles are off, the car can pull, feel weird to steer, and wear tires unevenly. An alignment shop measures the tire angles and corrects them.
Oil leaks mean the car is losing engine oil somewhere. That’s a problem because the engine needs oil to stay lubricated, and leaking oil can also make a mess or cause smoke. A mechanic usually tries to find exactly where the leak is coming from.
Transmission fluid exchange is a maintenance service where the old fluid in the automatic transmission is replaced. That fluid helps the transmission shift smoothly and protects internal parts. The idea is to refresh the fluid so the transmission works correctly.
VVT stands for variable valve timing. It’s a system that helps the engine open and close its valves at different times depending on how you’re driving. That can make the car run better and use fuel more efficiently.
A lifetime warranty is a repair coverage agreement that lasts a very long time. Here, the owner is saying the warranty covered the engine/powertrain, but not every small item.
Powertrain coverage is about the big moving parts that make the truck go—like the engine and transmission. The owner is saying the warranty covers major drivetrain failures, not everything.
“Bumper-to-bumper” means a warranty that covers lots of different parts. Here, the owner says it’s not that broad—some small repairs are on the owner, but big drivetrain problems are covered.
The transfer case is part of a 4-wheel-drive truck that sends power to both the front and back wheels. It’s a big, expensive drivetrain component, which is why warranty coverage matters.
Coil packs are part of the ignition system. They help create the spark that lights the fuel in each cylinder, and if they fail you can get engine misfires and a warning light.
“Dual cam” means the engine uses two camshafts instead of one—usually one for intake valves and one for exhaust valves. It helps control valve timing more precisely.
These are spark plugs made with platinum so they can last longer. If you replace them and still get misfires, it suggests the problem may be elsewhere (like coils, timing, or internal engine issues).
Term
diagnosi charge
A diagnostic charge is what a shop charges to figure out what’s wrong with the car. They may charge this even before you decide on the repair.
A compression check measures how well each cylinder is sealing and building pressure. Mechanics use it to find engine problems, but on newer engines it can be tricky because the engine’s timing system can change what the test shows. So a low number might not always mean the worst-case problem.
A misfire is when one cylinder doesn’t burn the fuel correctly. If the car says it’s cylinder five, that helps point to the parts that control that specific cylinder. The host is basically asking whether the new parts installed could be connected to the problem.
“Coils” here are the ignition parts that create the electricity needed for the spark plugs to ignite the fuel. If the coils are bad or not set up right, the engine can misfire. That’s why the timing after replacing them matters.
A misfire code is what the car’s computer logs when it thinks one cylinder isn’t working right. The important part is that it names a cylinder, which helps diagnose what’s causing the problem.
A compression test checks the engine’s internal condition by measuring cylinder pressure. If one cylinder has much lower pressure than the others, it suggests a mechanical problem inside that cylinder.
Cam timing is when the engine’s valve timing lines up with the crankshaft. If timing is off, the engine can run poorly or misfire, and simple tests may not catch everything.
Variable valve timing means the engine can adjust the timing of its valves. That changes how much pressure builds in the cylinders, so a simple compression test can be harder to read the usual way.
Waveform analysis is using a tool to record how signals change over time. Here, it helps pinpoint which cylinder isn’t contributing properly by looking at what comes out of the exhaust during cranking.
The tailpipe is where the exhaust comes out at the back of the car. Putting a sensor there lets the mechanic listen/measure the exhaust pulses to figure out which cylinder is acting up.
An ABS speed sensor tells the car how fast each wheel is spinning. If one sensor is wrong, the anti-lock brakes can act up, so mechanics check the matching wheel/sensor side.
A misfire is when one cylinder doesn’t burn fuel correctly. If it’s “cylinder number eight,” that’s the specific cylinder the engine control system is flagging as not firing properly.
Term
rust wing
This sounds like the mechanic saw a plug that looked unusually damaged compared to the rest. The exact phrase may be off in the transcript, but the idea is that one spark plug was in worse shape.
Term
sixteen plugs
“Sixteen plugs” means there are 16 spark plugs in the engine. That usually points to a very high-cylinder-count setup, so diagnosing one bad cylinder is a bit more involved.
Labor is what you pay for the mechanic’s time. The shop usually charges labor separately from the parts, so the final cost depends on how much work they had to do.
A misfire is when one cylinder doesn’t burn the fuel correctly. The engine can detect this and log a code that often identifies which cylinder is misfiring. Common causes include ignition problems, fuel issues, or internal engine sealing problems.
Variable valve timing is a feature that changes when the engine’s valves open and close. Since the valves might not be in the same position every time you test, it can affect the pressure numbers you get. That’s why the host warns that the compression test needs to be interpreted carefully on these engines.
A “Chrysler dealer” is an authorized car dealership that services Chrysler vehicles. If you’re under warranty, the dealer may decide whether they cover the diagnostic work or charge you if the problem isn’t covered. The host is using this to explain how warranty coverage can affect what you pay.
An extended warranty is extra coverage you buy after the original factory warranty ends. It’s supposed to help pay for repairs, but the company that pays for the work can sometimes make the process slower or more complicated. The host’s point is that it may encourage shortcuts instead of careful diagnosis.
Cars have a communication system that lets different computers talk to each other. A CAN network bus communication fault means that message traffic isn’t working correctly. That can cause weird problems and warning lights, and it often takes careful troubleshooting to find the real cause.
Concept
diagnose whatever the problem is
“Diagnose” here means figuring out the real reason something is wrong, not just guessing. The host is saying that if a shop only has a short amount of time, they may not check everything carefully. That can lead to fixing the wrong thing or not fixing it completely.
The heater core lines are the hoses that move hot engine coolant into the heater box. If the heater isn’t working, checking or disconnecting these lines can help you flush the system and find the blockage.
Spark plugs are the parts that create the spark that lights the fuel in each cylinder. If the plugs don’t spark correctly, the engine can misfire or won’t start.
Load testing means you test the ignition system while it’s being stressed, so you can see problems that don’t show up during a simple check. In this case, the spark looked fine at first, but failed once the system was loaded.
A “gap” refers to the spark plug tester’s electrode spacing, which determines the voltage required to jump the gap. Using a specific gap (here, “three sixteenth”) is part of load testing to see whether the ignition system can produce spark at a harder requirement.
They’re explaining that spark behaves differently inside the engine than it does in open air. So a quick spark test can be misleading if it doesn’t match real cylinder pressure.
The ignition control module is the part that tells the ignition coil when to fire. If wiring between the module and coil is damaged or shorted, the engine can lose spark and shut down.
Term
order repair
They’re talking about fixing a problem by testing step-by-step instead of randomly replacing parts. You check the basics first, then you only move on when the tests tell you what direction to go.
Fuel pressure is how strongly the fuel pump pushes gas to the engine. If it’s too low, the engine may not start or may run poorly because it isn’t getting enough fuel.
A flash test is a quick way to see if an electrical signal is actually happening. Instead of guessing, you use a light/LED to check whether the computer is sending the right on-off signals.
The PCM is the engine computer that tells the car how to run—when to inject fuel and when to fire the ignition. If the PCM isn’t outputting the right signals, the engine may not start even if some parts are working.
The crankshaft position is how the computer knows where the engine is at in its rotation. If the crank signal is wrong or missing, the engine often won’t start.
The ECU is the engine computer. In this case, the signals were getting into the computer, but the computer wasn’t sending the correct outputs to make the engine run.
An ignition coil is the part that makes the spark that lights the engine. If it’s bad, the engine can start misfiring and running rough.
Concept
road downhill is paved with ice
It’s a way of saying that on a downhill road, ice can make the tires lose grip fast. When traction is gone, it’s easy to slide or hit something before you can react.
A tire plug is a rubber piece that seals a puncture in a tire. It may not help if the tire has a bigger problem or damage in a different spot than the original puncture.
The sidewall is the tire’s outer part on the side of the wheel. If it gets damaged where the sidewall meets the tread, the tire can start leaking and fail.
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Join the Conversation live every Saturday from two to four pm Eastern by calling eight five to five five six zero nine nine zero zero. That's eight five to five
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start your engines. The Car Doctor is in the garage
and ready to take your call.
When is it too much?
What is it?
Jeez? It's just like you're opening up Pandora's box and
is it Your responsibility is the mechanic to tell them that?
You know, when you get a new customer in the shop, it's it's usually because the last person or persons or shops or shops couldn't satisfy them, or the person's a nut.
I mean, there's no other way to say it, right, It's it's one of the other. It's they couldn't fix
the car, or the person didn't want to let them fix the car, and the person was unreasonable. Marion brought
me her twenty ten Toyota uh this week one day, you know, first time I'm meeting her, and very reasonable, very nice. Just you know, why can't the last two
shops fix this car? I don't understand it because it
had a check engine light on, it had traction control lights.
You know, Toyotas do that. They'll they'll they'll set a
fault code and like a lot of the Japanese products out there, you'll set one fault code and it'll turn on all the lights and it looks like a Christmas tree on the dashboard and you know, yeah, okay, fine, you know it's going to cost a couple hundred bucks.
We'll you know, get into it. We'll start, we'll take
a look and let's se yeah, okay, good, very reason.
I'm thinking. You know, you're as a mechanic, you're kind
of looking over your shoulder. You're saying, you know, is
there a nut here, but you know it's it's you're looking, but you don't see it. So this twenty ten Toyota
came in and you know, as I always do, I give it a once over and scan it for codes, and it had a P zero four fifty six small evaporative emissions League and some preliminary diagnosis started pointing towards the charcoal canister, the canister assembly. Well, it's not that
the canister assembly was bad. The vent valve which is
actually on the canister, but the bolts were rusted to the case because it's it's sixteen years old, and it's had one hundred and fifty thousand miles and it's had a hard life. And you know, what are you gonna do?
Take it apart and just put a vent valve in it.
You're gonna take it apart, put a canister in it.
I mean that would be logical, right, Proximity of repair and consistency of repair and the ability to actually get to something, that's what you're gonna do. But to get
to that, and here comes the you sort of got to sneak it out past the exhaust system or lower the exhaust system, one or the other. And lowering it
is generally easier because it's pretty tight in there. It's
you know, the geniuses at Toyota. But the canister above
the exhaust, above the heat shields, so you have to take down the exhaust, the heat shield and then you're looking at the canister because after all, charcoal canisters on toyotas they never go bad, you know, like the sun's going to come up tomorrow, what day is it? And
I look at this Toyota. I'm looking over the rest
of it, and it's it's a little crunchy, you know, it's it's seen some better days as far as rust is concerned. You know, it's not quite I need a
tetans shot to look at it. But it was sort of,
you know, encroaching on that. It was sort of becoming
the uss rostolium. The more I looked at it, and
you know it is that what you want to do?
I mean that thing had so much rust on the back of it. It was like a museum. You know,
you could have taken people through it and said here here's what looks like. You know, you know, could have
charged a quarter a route. So, yeah, it's getting worse
the more I look at it, and then I noticed up front and I noticed this when I started it, I heard a little bit of an exhaust rumble and I look and where the front exhaust pipe meets the center exhaust pipe, the flan just kind of hanging on, you know, like it knows not to let go for something bad will happen. And you know, in bottom line,
in order to do this charcoal canister that I think I'm gonna have to do, at some point, I'm gonna have to lower the exhaust or I'm gonna have to risk leaning hard on the exhaust to lean on the heat shield to get the heat shield out of the way, which is rusted in place by the way, to get the canister down. So you know, it was that it
needed three tires. The tires were getting kind of thin
in the skin. It had a couple of oil leaks.
You know, I was disappointed. I sort of hope the
oil leaks would reach the back of the car because it would slow the rust down. But you know, it's
like that stuff just doesn't generally happened. So I did
what I usually do. I tell somebody what they need
to know, not what they want to hear. And Marian
absorbed it. She you know, I think she understood it.
From her perspective. I think she was shocked that she
had a mechanic that was explaining things. I think that
was the bigger issue. But in an event, we you know,
I told her what was going on. She was going
to call her husband, and I hung up the phone.
We hung up the phone and I counted, and within three sixty second cycles the phone rings and it's the husband, Tom Thomas. Tom, and I explained the whole thing to
him and he got it and he said, you know, he said, Ron, the biggest thing is, he goes, I'm really probably going to replace the car because you know, it's sixteen years old and my wife's riding around in it.
I want to get her into something nicer. You know,
do you think it's worth fixing? And I took them
down the path of all the potential of what I see.
You know, it's almost no guarantees, but I'll take out the crystal ball for a paying customer and give you my best nickels worth of free advice. And you know,
he said, what would you do? And I said, I'd
replace the car. I you know, I think you're I
think you're barking up the wrong tree. It's it's tired.
In a lot of places. The rust is eventually going
to take the back of the car to which the front is attached. So at some point it's going to matter.
And you know, if you're ready to replace it, let's replace it. Let's not you know, fool around with this.
Can you get it through inspection?
Well?
Yeah, you know in New Jersey, all right? And I
don't know if any statuoter law in the books to prevent you from doing this. You clear the codes, you
run a drive cycle. If it passes the drive cycle
doesn't set a fault code, that car passes inspection because there's no law on the books in the in the great wonderful Weak Care State of New Jersey that says you you can't inspect the car because you think it's going to set a fault code. It has to be
a hard failure. It has to be right there in
your face, the lights on the fault is there. It's
not we think this is going to happen. So I said,
you know, I need about an hour of time I got to run a drive cycle. I explained what an
OBD two drive cycle was, and he said fine, and I you know, after lunch, I went out, I cleared codes, and I went out for a road test. Sure enough,
I got all the monitors to run. Sure enough, I
had no fault codes, which tells me this is going to get even uglier because it's it's an intermittent failure.
And you know, where do you? Where do you? Where
do you begin? And I've got a few ideas. Had
I had I had I was supposed to have begun if I said that, right, But bottom line, and I guess this is my point that you know, you never know what's going to commit on a Monday. Mondays are
always an interesting day. I ended up running monitors. I
got the vehicle to pass inspection. I got the vehicle
into condition for inspection. I should say it like that
in that once we ran the New Jersey Motor Vehicle inspection.
Plug the machine in, go through the steps, vehicle passed, and I explained to the customer, you know what, this is a random fault. Is the like going to come back?
I don't know, but my recommendation is replace the vehicle.
You know?
Is that a mechanics obligation? I think so. I think
that's part of what we're supposed to do. We're supposed
to guide people because people are basically clueless when it comes to cars. In a lot of cases, they just
don't see. They just don't see what it is and
what it takes for a vehicle to exist. So I
guess the point of all this is, you know, find a mechanic you trust, find somebody you can talk to, be reasonable, try and work with them. See if they
work with you, and you never know, great relationships can come out of that. I'm Marion's new best friend. Her
and her husband Tom. They're both very happy. They're out
car shopping. They're going to bring me a car, they promise,
within the next week to ten days, and we're going to move on to something else because otherwise we're going to get into exhaust canisters. Three tires going to become
four wheel alignment. There's a couple of oil leaks, and
before you know it, we'll put four grand or five grand into the sixteen year old Toyota with one hundred and fifty thousand miles on it, which is okay, But if mama wants a new car, mama's got to get a new car. And that's sort of the rule to
live by. So just something to think about. Right, just
when a shop says no, you wonder why they say no.
Do they give you a good reason? Do they explain, well,
you know, maybe it's not worth fixing, because always look for that, because because that's always a very important part of the order repair process. Eight five five five six
oh nine nine zero zero eight five five five six oh nine nine zero zero. I'm Ronningeny in the car doctor.
I'll be back right after this. By the way. Two
new videos up on the YouTube channel this week. One
is the Mala trans fluid exchange process. This that we
are diving into this year. We're going to be throwing
up a bunch of videos talking about transfluid exchange and why on various vehicles. And the other is talking about VVT.
It's a very very basic video explaining variable valve timing and we talk about the process of the procedure and the operation of and WHYVVT. Very light, very quick video,
sort of like a three to four minute primer, and we're going to try and do something more detailed, more in depth also this year. But they're both up on
the YouTube channel. If you get a chance to get
out there, take a look at them. If you like them,
like them, if you don't like them, don't like them, put a thumbs down, put a thumbs up, whatever, put a comment. Let us know. And you know, if you
want to share your thoughts on anything else you want to see, you send me a note Ron at cardoctorshow dot com and I'll be sure to give it a lot of very careful consideration because we're here for you guys.
And of course, as always, you know, don't forget our Facebook page. And if you're subscribing, if you're a podcaster,
and if you're not a podcaster, tell your friends, tell your family, subscribe, hit that like button, hit that subscribe button.
Ops us.
The numbers help drive us and drive the business side of radio. So let's go over to Frank in Tennessee.
See what's going on here and see what he's driving eleven Dodge Ram pickup Frank, what's going on? How can
I help?
Hey, sir, thank you very much for taking my call.
We want to know to get started here on the I'm not wealth in two thousand and eighteen July twenty eighteen, I got eleven Dodge Ram five point seven Hemi engine In twenty eighteen, I had a code check engine like so it took it in and I got a lifetime warranting one. So I took it into the.
You've got a lifetime You've got a lifetime warranty from who, from Chrysler Kwysler. So you you bought this as a
used vehicle, no brand new, brand new in eleven, bought it, yes, sir, okay.
And in twenty eighteen, how many miles did it have on it?
Then?
Just out of curiosity.
At do down in eighteen or in eighteen eighteen, malage was about seventy eight thousand, five.
Hundred, Yeah, seventy eight thousand miles. And how many miles
does it have on it now?
Now? One hundred and sixty eight thousand?
Okay? So you bought it from the dealer in writing,
they gave you a lifetime warranty on the engine or the.
Whole truck, the whole truck. I got the powertrain, powertraining,
lifetime walking bumpered okay.
So now, well not what we would call bumper to bumper.
If a bulb burns out, you're you're you're paying for it.
If it needs breaks, you're paying for it. But if
a major drive train component engine transmission transfer case were front of rear axle blows up, it's covered electronics. Okay,
all right, So here we are in twenty eighteen, and the truck turns on a check engine light. I assume
you're going to tell me.
Correct, and it's it's.
Said some sort of a fault code.
I changed out to all the plugs because that's that's wear and tear. So I went and did the all
the plugs. I also went and did all the coill packs.
And as soon as I started up, boom, check engine like came back on.
Okay, who's time? Whose brand of coils did you? Whose
brand of coils did you use?
Oh geez, you're talk in twenty eighteen. I'm old.
Well I know that, But what do you think you get them? Well, you think you think you went and
bought them from Chrystler. You think you bought them online? Okay,
all right, So you had you had a missfire, you said, a check engine light. You said, a missfire on some cylinder?
Correctumb five?
All right? And then what'd you do took it to?
After I saw that that then it's inside the engine.
So I took it to a question garage over here in uh Tennessee, Knoxville, Tennessee, and they went and took it down. They said, yep, they're going to have to
do the engine. So he did the camshaft, all the tapts,
both heads camshaft. I'm looking now. I thought they had
just one cam in that, but I found out there's two cams. She said, dual cam. Well on my paperwork
here in twenty eighteen, they replaced the left side camshaft one, not the right side. So after I saw that, I
got a coat in code check engine light on check engine number eight cylinder. So only got oh that's and
one hundred thousand miles of my plugs, double dual platinum plugs.
So I said probably not, maybe, maybe not. So I
just went ahead and took it out to the crisis rids two hundred and seventy five dollars for a diagnosi charge.
And then they said at the plug. I said, wait
a minute, how about doing a compression check and the plug all the engine, do the whole engine and do a compression check. Because I found out that the cams
on the eleven rams, those two five point seven engines had bat cams at them. It cost the country a
lot of cams were being replaced, so I thought they did both cams. They didn't, so that's why I went
and had them do it out there since I got lifetime warranty, and they said, nope, cams find But they also did one compression check on just number eight, not the whole engine. So in number eight I have ninety
pounds compression.
Which isn't enough. But there's a whole argument about whether
compression checks are accurate anymore variable variable valve timing engines, compression checks don't necessarily work because where's the cam when it's going to do that compression test and it can affect it. So I mean, listen, can I comment on
something here?
Go ahead?
Why after replacing the coils and the you know, the next moment you said, you started it up and you got to check engine light and a misfire reported on cylinder five. Why wouldn't been back in eighteen Why wouldn't
anybody think to themselves, could it be related to the new parts we had just put in?
True?
Did anybody do any diagnosis there?
Well that the shop did right now?
Is that the original Chrysler dealership where you bought it from? Yes, okay,
Was that warranty policy a Chrysler policy or was that unique to that dealership Chrysler, And it says on it Chrysler. Yes,
And you could call there's probably an eight hundred number on that warranty policy. You could call them up and
they'll tell you. You know, mister Frank, you can go
anywhere in the continental United States and get that warranty correct.
And I'll already try that out and it has worked.
Okay, Okay, Yeah, I'm just wondering in Pennsylvania.
That's a heck of a warranty. Brother, Yes, that's that
truck's going to be around until it rusts out through the frame rails. So I'll tell you what, Frank, stay put,
stay where you are. We'll come back. We'll finish up
with this because I think this is going to be a good story in the long run. So on the
backside we'll get to you. Don't go anywhere. I'm Ronning
Nanny and the car doctor. Frank and I will both
return right after this. Stay put.
From the seat streets to the open route in night.
If you ride nes hell.
Ron will keep you rolling right.
Yeah, he's the car Frank.
You're still there, sir, so let's recap this. You bought
a twenty eleven Hemi and twenty eleven brand new from the dealer. They gave you a lifetime warranty on powertrain, engine,
trans differentials, axles, et cetera. Twenty eighteen, about seventy thousand
miles you had done plugs and coils, and at that point, right on the initial startup, it set a misfire code on cylinder five I think you said. Took it to
the Chrysler dealer. They said, hey, you know, look, you've
got a bad camy. In twenty eleven there was one
singular cam down the middle. That was the infamous MSD
multiple cylinder problem camshaft issues they had. And it's been
good for about thirty thousand miles, and here we are, No, actually it's longer now, right, yes, ninety thousand and now it's setting a misfire code on cylinder number eight.
Correck.
And back in twenty eighteen they did a compression test and it was ninety psi or now they did a compression test and it was ninety psi.
Last month, yes, correct today, So so you know, I'm not going to say ninety condemns the motor but if I've got a question about one cylinder where you know, if I've got a problem on eight and I'm checking compression.
And I got ninety and I want to, you know, is that good or bad? What do you think the
easiest way to figure it out is really quick and easy? Well, no,
why don't we just go check compression on a quote unquote good cylinder? What's known good? Right?
Ye?
Right?
If we don't do all weight cylinders, let's.
Do let's do at least one. You know, compression testing
is kind of an archaic thing, as hard as that is to accept, and I understand that, you know, we do.
We do a lot of different ways now and a lot of the problems are because cam timing has changed.
Variable valve timing has changed cam timing and caused us to rethink the compression test. And there are shops now
and they've gotten quite good at it. They'll do things
called waveform analysis. They'll put up a sensor in the tailpipe,
watch the engine crank over. They'll scope out, you know,
exhaust puffs or air puffs and tell you here's the weak cylinder, here's the good cylinder, and so on. But
you know, I don't know that the ninety PSI bothers me.
I'd be curious as to why they didn't go check one of the other cylinders. Yes, you know, that's just okay?
Is it good or bad?
Look?
I talked to shops all week long, right, talking to one fellow this week. He's telling me he's got a
problem with the left of your ABS speed sensor. He's
not sure about the pattern he got, and he's been working on it for three days. And finally I said,
why don't you go look at the right rear?
Oh?
Yeah, I guess I could do that. You know, if
you've gotten known good on the car, let's go look at known good, you know. Let's let's go see what's working.
So anyway, back to your issue. So here you are
one hundred and sixty eight thousand, and now you've got a misfire on cylinder number eight. They're telling you it's
not compression. What are they telling you?
It is? Plugs? They said they found one plug that
was out of all sixteen plugs, they found one one plug that had a rust wing. The one plug.
Yeah, so the plugs, okay, so the plug it's got two right, So the plug's breaking down, right, so did they put plugs in it?
Yes? I had uh wow, was there was either eat
up two hundred and seventy five dollars or let them put it in for parts was two seventy nine. But
they also labor, so got me for labor.
Right, So now you're one thousand dollars into this quidge and is cylinder number eight fixed?
Well, the checking's life not on. But then I went
to a friend of mine has got a local shop shop and.
It's it's it's showing appending, it's showing appending number eight or it's showing appending misfires.
Yeah, and they ran out of thing and says compression should not be less than ninety less than one hundred.
Yeah, and I would agree with that. I think I
think ninety is. But again, you know, questionable meestionable because
compression with variable valve time, if we open or close the valve later early in relation to piston position, we're going to get an accurate compression test. So you know,
it's it becomes so much critical if we're going to do that, let's go sample two or three other cylinders if we don't want to do them all. So I've
got two I've got two comments here. One, the two
seventy five for the diagnosis. Was this done at the
Chrysler dealer where you purchased the truck and the warrant, and that gave you the warranty?
Correct?
Okay? So in the confines of that warranty and the
fine print somewhere, how does it say it will handle diagnosis only if.
It's found that the problem is under the warranty. If
it's not under warranty, then I got to pay the two seventy five.
Okay. So they're saying because the compression is quote unquote.
Good, Well what question? They were says, it's with the
inspects of the Klaiser Okay, as she said, ninety psis with inspects.
So I guess when you go back on Monday and you say, hey, when you pop the fault code and it says cylinder number eight, I guess we're gonna watch them meet two seventy five, aren't we?
Yes? Right?
Okay, because you know that's gonna happen, and we have to do.
Another compression check all all white silvers. Like I asked
it too, Well, they won't. They won't.
They won't do that because they're going to base it on maybe they've seen you know, maybe they see thirty engines a week and they know what the number is.
I don't. I still don't trust it. I don't know
that I would accept the compression test, not on anything anymore today. And if I have any questions, it takes
me another fifteen minutes to you know, there's a there's a there's a part of this here that give the customer confidence, make you feel good about it. Right, you
know you purchased it from them, You come back to them, you're just asking, hey, fix my truck, fix it right, tell me what else it needs?
Right?
Dealership changed hands. The first original dealership was good people. Right,
and now now it's more corporation now, right?
And how did I know that was going to be the last part of our conversation today?
You and I? Right? You know how true?
Listen? Remember remember Mama telling you that you get what
you pay for in life?
Exactly?
You know that that that extended warranty, that wonderful warranty. Frankly,
I don't. I don't like to deal with extended warranty
companies either. A pain in the neck. They usually give
you an hour to diagnose whatever the problem is, whether it's a simple, you know, flat tire or an involved can network bus communication fault problem. And it also encourages,
in my opinion, technicians to work faster and sloppily and and not do a thorough correct diagnosis. And it's it's
it's it's just difficult. We deal with extended warranty companies.
When we do, I charge an hour just to talk to them because I'm usually on the phone for two because it eats up the clock. And it's it's look,
I'm not scolding your brother. You know what, they sold
you to the truck and hey, we'll give you a lifetime warranty, but somebody somewhere is paying for that warranty, and you know it. It sounds like these guys don't
want to deal with it anymore. They don't do that anymore.
Now you notice, Oh yes, it is not right, it's not even right.
And you buy a new truck, now it ain't they're one year right, right?
Yeah, Well usually powertrain is three thirty six or five and sixty or something. But you know there's there's a
better warranty. It's just lifetime. Because you and I, you
and I both know we're both smart enough to know that nothing can last a lifetime without having a failure.
And you know at that point that's right, it's.
That's why I was guarantee I was going to keep the truck. I got a truck that out of your life.
Right, So sorry, Kitto. I wish I had some better
answers for you. All right, but I think you got
I think you gotta be ready for when that misfirefolt pops on. And if it is cylinder number eight, you know,
well maybe it is compression related. And if it is
compression related, get your two seventy five back.
Yeah, I'm gonna I'm gonna be running, take some trips with it. And right, so let's to plug again.
Yep, all right, Frank, I gotta go. You keep my
number handy though. You need me, you call me eight
five five five six nine nine zero zero. Running of
the Car Doctor. We are coming back right after this.
Welcome back run Naming the Car Doctor. Let's go to
Bill in Long Island. Bill, welcome sir, How can I
help you?
Hey brother, It's good to hear from me again.
Oh hey, Bill, how are you now? I know who
this is?
So yeah, Bill Man with the with the yep yep, yep.
So you want to tell the story you want.
Me to, Yeah, I could tell it. I could definitely
tell it in a nutshell.
Go ahead tell it, my cousins. Two thousand and one Blazer.
It's got no heat. We disconnect the heater core lines
from the firewall. We flushed out the heater core. We
started backed up. We've got great heat, and you know,
while we're flushing, we had some garden hose water just kind of spray around an injured apartment, nothing crazy, and she all of a sudden, the car shut off and it wouldn't start again. So we pull it in. We
go through spark fuel. It's got what appears to be
excellent spark. It's got fuel pressure. Everything's firing at the
right time. All six spark plugs hanging out of the
side of the motor grounded to the engine, and all six appear to have for what looks like strong spark.
But at the end of the day, it wasn't enough.
You and I talked about load testing the ignition, so I put I put the tester at you know, three sixteenth gap. We loaded the ignition. Then I lost the
spark altogether. That actually made it a lot easier because
when you know, if you're chasing spark and fuel and now you're chasing a ghost at least with no spark, I can get to the flow charts, and I was able to trace it back to a weak ignition coil.
So even though we had good spark, you know, you and I talked about the just like a boosted car.
Right, well, right, because the difference is in a cylinder, a cylinder at one hundred and fifty psi, the ignition system was under more duress than an ignition system trying to fire across the gap of a spark plug an atmosphere.
If atmospheric pressure is you know whatever, it is, fifteen pounds, whatever the magic number is, depending upon where you are, you know, it's it's it's just a very different environment.
So what'd you learn out of our phone calls?
Bill, Well, one thing we learned is seeing excellent spark doesn't mean you have excellent spark. We got to do
the proper little test load di ignition, and uh, I'm trying to think what else I did to this thing.
You know, at the end of the day, somebody had spliced in a test wire to the white wire with a black tracy that goes from the ignition control module to the ignition coil. So while I was posing it,
water must have found that open metal of that connector because it was open and that was the wire directly going to the coil, and.
It shorted that.
So we shorted the coil with the water and lost, you know, most of the sparks.
So I guess, I guess the I guess the answer really is, it's it's just basic testing is still basic testing.
I remember you went through fuel pressure, you went through a bunch of.
Stuff, and yeah, it really threw me because you know, the visual spark.
Was really good.
Yeah, just just well. And you know it's funny because
I was gonna I was gonna open today's show and I'll probably do it next hour talking about how you never assume right assumes it assumes a dangerous word. But
order repair is all about testing. And I can't tell you.
It's easy for me to sit in my chair here and I hope it doesn't sound like lecturing, but to tell you guys, you know, basics, basics, basics, always always do the basics. I can't tell you how many guys
I talked to did you do this?
No? Why?
Well, because you know, check fuel pressure, check spark, check fuel pressure, basic simple stuff. And then and then as
the problem because one thing I've learned is the problem will always get more complicated as it needs to, because as it starts to pass or not past basic testing, you'll know which direction to go. So but listen, I'm
glad you got it something.
You know.
One other note on these things. Yeah, you know, when
I originally put the coil in, it didn't fix the problem.
So that's when, you know, I kind of got lost there.
So that's when I made the I made a flash test out of a one ninety four LED bulb. Just
run it to positive and check the ground signal coming out of the camp sense of the crime answer. I
checked them at the wire to the PCM. The you know,
the camshaft shot the LED off six times or I'm sorry half half the time, and then one time, so you know, once for revolution, and then the crank dancer shot it off, you know, six times for a revolution.
So all the signals were ending at the ECU but weren't coming out of the ECU. So at that point
I put the original PCM back in the car and.
It started right up.
But at the end of the day I had put a Junkyard PCM in that was faulty and that took.
Us off the track right right. That's why it's.
Now we're back to the original and the.
Original problem, and the original problem was a bad ignition coil, Yes, sir, just remember this. It's it's like I keep telling you guys,
the road downhill is paved with ice. So and it
is because it happens really quick.
Bill.
I appreciate the call, and I'm glad you got it solved.
I'm ronning any and the car doctor. We're back right
after this. Yeah, I'll listen.
I'll tell you a reason why you never assume okay, yeah, order repair is it's probably the hardest thing you'll ever do in your life because you cannot be emotional, you cannot be.
Tired, you cannot be laid back. You've got to be
attention driven, focused, staying on the task right because you're trying to solve problems most of the time, and the least the simplest things can sometimes thirty for a loop, we had a customer with a twenty four Lexus, fairly new car low mileage thirty thousand miles. She goes and
visits her daughter a couple of towns away beginning of last week, and when she's turning into the daughter's driveway, she cut the corner kind of tight, so on the right side she crushed, I mean crushed the passenger side front door against this big pile of ice and snow at the beginning of the driveway. And it's probably easily,
it's easily three thousand dollars worth of body damage, all right, just caught it on the snow bank the wrong way, you know, visited with the daughter, got over the g I you know, screwed up my car thing, and came home.
And she called me Monday morning because now the car had a flat and you know, gee, we you know, those tires were good the last oil change. And you know,
she's telling me the whole story. And she said, well,
this is the tire you put the plug in the last time I was in because I had picked up a nail.
All right.
She brought the car down. She pumped some air into
it at home, brought the car down. I looked at
it had nothing to do with the plug. My tire
repair was fine. The sidewall and the tread where it
comes together. At that corner, there was a hole. I
take the tire off, I fill it with their water's coming out. Water's coming out, Little chunks of ice are
coming out. Ice had penetrated the tire. It was frozen.
Two days later, as it warmed up, the car started to leak and while La we had a flat. I'm
ronning any in the car doctor. The mechanics aren't expensive,
a priceless.
Hey, he's a car doctor.
Car advice to ride
About this episode
Fault codes, rust, and warranty limits all shape how Ron Ananian diagnoses problems. He walks through a Toyota EVAP repair where a P0456 points to the charcoal canister and a rusted vent valve buried above exhaust and heat shields. He also explains why clearing codes and running an OBD-II drive cycle can temporarily pass inspection even with intermittent failures. Later, he digs into misfire/compression testing pitfalls on variable valve timing engines, and contrasts careful testing with rushed diagnosis under extended warranties.
