2015 Audi A3 Charcoal Filter

Hi, it's Mark.

I'm here with Bernie Pawlik, Pawlik Automotive in Vancouver, BC, Canada.

Vancouver's best auto service experience.

We're talking cars.

How are you doing, Bernie?

Doing very well.

Today's guest is a 2015 Audi A3.

What was happening with this vehicle?

So the vehicle owner's complaint was that when he'd go to fill his fuel tank up, he

couldn't put any gas into it because as soon as he'd start filling it, the nozzle would

click off.

Fuel nozzles have an automated system if the pressure's too high, I guess, feeding back

and thinks the gas tank's full.

So anyways, it had been going on for quite a while, but it was getting worse to the point

where he couldn't even put any more fuel into the vehicle or barely anything.

So just hold the nozzle on, it would just click off.

Hold it and you'd get a few drops of fuel here and there.

So it was pretty critical.

So that sensor in the gas feed nozzle is detecting gas vapor pressure because it's not fuel coming

back if the tank is empty?

I think it's detecting there's too much back pressure.

I assume that's the way they work.

I'm not an expert on fuel nozzles, but they seem to work pretty accurately when you put

it in a tank and you put on auto and you go to fill it once it reaches a certain fullness

level, it just clicks off.

So anyways, that was happening.

There was something wrong with the car.

We see it from time to time on various vehicles.

Not too common.

And all because gasoline is a very fumable, flammable, fumable, flammable and fumable

substance.

Exactly.

Yeah.

So there's our beautiful car 2015.

So it's over 10 years old now, but still looks like a brand new car.

Well maintained, low mileage too.

So this is an important thing.

So right on the gas cap, do not top off.

So what's supposed to happen is when you fill your car and this is not just for

outies, this is for every car.

When the gas nozzle clicks off, you don't go, oh, I think I'll add a couple of more

dollars worth of fuel or I'll top it up or no, it's $49.50.

Let's make it $50 even.

Don't do that.

Because what happens is you get expensive repairs in the end.

You can get them.

And this is the case with this Audi.

So even though your car may not say do not top off all cars, if you read the owner's

manual, it will say that somewhere.

It's just even more acute on this Audi.

So they know there's actually a kind of serious issue with this system, the way

it's designed.

Now we're looking at the other side.

Is that right?

Yeah, we'll just jump right to the repair.

So the owner had taken it to an Audi dealer and they had recommended

replacing the fuel tank, filler assembly, charcoal canister, everything.

The estimate was enormous.

What?

Yeah, the fuel tank, fuel filler, neck, the whole nine yards.

And there's a lot of dealerships that do good work, but sometimes their repair

recommendations are just a little too, let's just change everything.

And it was a lot of money, like multiple thousands of dollars to do all the work.

So he brought it to us for a second opinion.

We had a look at it, diagnosed it.

And from our repair research and information, the most common problem when

this happens is the charcoal canister gets flooded full of fuel.

And that's what's causing the thing to click off.

I said, Hey, you know what?

Maybe you do need a fuel tank or filler neck, but let's do this part first,

which is still expensive and substantially cheaper.

So the green arrow is pointing to the fuel tank filler neck.

Yeah, that picture we looked out of the fuel cap, basically that fuel cap is

just right above where that arrow is.

So this is sticking outside the car.

This is inside the wheel well.

Yeah, this is inside the wheel well with the wheel cover off.

So that's the fuel filler neck.

And right below that arrow, you can see a plastic pipe with an elbow

corgade pipe.

That's the vent pipe to the charcoal canister.

So we'll talk about what the charcoal canister is in a minute, but essentially

there's supposed to be no liquid fuel inside the charcoal canister.

And of course, you can see how high up on the filler neck this is.

It's pretty easy if you were to keep topping the fuel up further to be liquid

in the line, and that would end up pouring inside the charcoal canister.

OK, as we were discussing before we started, I've never heard of the charcoal

canister. So what the heck is this thing?

The charcoal canisters basically there to trap gasoline vapors.

If you've ever looked at on sunny, hot day, gasoline is evaporates.

It's very volatile liquid.

And that's actually bad for the environment.

Like really bad creates a lot of smog and pollutants.

Auto engineers many years ago discovered that if we can trap those gasoline vapors,

it prevents it from getting out into the air and pollution that's associated with it.

So what the charcoal canister does is it performs that function.

The fuel system is now sealed.

So when you put fuel in your gas tank, you put the cap on that system sealed.

There's nothing that can escape into the environment, into the atmosphere.

Any vapors that come out of the gasoline go into this charcoal canister

and then the engine will actually at certain points will actually suck the vapour out

and burn it up in the engine.

I believe that's what that little white pipe that you can see there does.

That actually goes up to the engine and is burnt.

The computer controls when the canister is open.

It's called a purge valve.

So here we have the new charcoal canister OEM dealer part,

which is the only place we were able to source it from.

And if we look at one more picture further up, we can see the old one,

which looks exactly the same.

But the interesting thing is when we removed it from the vehicle,

you could feel the weight of fuel inside it.

You could feel it was saturated with liquid.

It was just noticeably heavier than the replacement unit.

But it was even apparent even before we had the two to compare them.

Something feels heavy on this thing.

And it's not supposed to actually have fuel in it.

It's supposed to be vapor only that the carbon is catching.

Is that right?

Yeah, the carbon is a sponge that kind of captures the vapor and retains it.

So this is the thing when, again, when you're fueling your vehicle up,

when the gas nozzle clicks off, stop right there.

Unless you've got a problem, of course, like this vehicle had,

in which case you have to nurse the fuel into the system.

But to void it, if you just stop filling it when the cap clicks off,

don't worry about the extra 50 cents surrounded off.

Yeah, or dollar or whatever.

Sometimes you can cram an extra dollar or two, but it's not really worth it.

When you add it all up and often like to do the math when I think of cars,

this vehicle has got 61,000 kilometers.

How much does this repair cost?

You don't save any money by putting more fuel into it.

It's just prevents you from having to fill up more often.

Lately more often in the life of the car, maybe two or three times more time.

Yeah, two or three times more, which is nothing.

It's always tempting if there's a super duper sale on the price of fuel in one

station, but it doesn't happen very often, especially in Canada.

Not anymore.

Yeah, not anymore.

So if you're looking for expert ID repairs in Vancouver,

the guys to see are at Pawlik Automotive.

You can reach them online at pawlikautomotive.com.

You can book your appointment right there, or you can call them 604-327-7112.

Pawlik Automotive in Vancouver, BC, Canada.

Thanks so much for watching and listening.

Thanks, Bernie.

Thank you, Mark.

Thanks for watching.

Audi A3

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