fuel trim
Fuel trim is how the car adjusts the amount of fuel it uses based on how much air is coming in. If it's not set right, the car can use too much or too little fuel.
Fuel trim refers to the adjustment made by the engine control unit to the amount of fuel injected based on the air-to-fuel ratio detected by the mass airflow sensor. Issues with fuel trim can lead to over-fueling or under-fueling the engine.
Hear It Discussed
"Fuel trim was at 20, between 18 and 22%. I was a little nervous about that."
Can The 911 GT3 S/C Be A Real GT3? — The Carmudgeon Show w/ Jason Cammisa & Derek Tam-Scott — Ep 234 The Carmudgeon Show
"Well, yeah, but if you go messing with an intake system or an exhaust system on a vehicle, sometimes that's too much for the fuel trim to overcome."
Trusted Automotive Advice Personalized for You Too Under The Hood show
"So you know, you're gonna look at fuel trim, You're gonna look for vacuum leaks, You're gonna go do a basic, Yeah, throttle body cleaning and try to do some resets and adjustments as a starting point."
Ron Ananian, The Car Doctor - Classic Car Doctor - October 10, 2015 - Hour 1 - Audi Codes, Airbags & Frozen Custard Ron Ananian The Car Doctor
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Episodes Mentioning "fuel trim"
Ron Ananian, The Car Doctor - Classic Car Doctor - October 10, 2015 - Hour 1 - Audi Codes, Airbags & Frozen Custard
Ron Ananian The Car Doctor
Ron Ananian, The Car Doctor - Classic Car Doctor - September 26, 2015 - Hour 1 - Volkswagen in the Hot Seat: Emissions Scandal
Ron Ananian The Car Doctor
Ron Ananian, The Car Doctor - May 9, 2026 - Hour 1 - Why Your Car Is Quietly Burning More Gas
Ron Ananian The Car Doctor
Trusted Automotive Advice Personalized for You Too
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Ron Ananian, The Car Doctor - April 25, 2026 - Hour 2 - The Cost Of Not Knowing What's Broken
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Can The 911 GT3 S/C Be A Real GT3? — The Carmudgeon Show w/ Jason Cammisa & Derek Tam-Scott — Ep 234
The Carmudgeon Show
Ron Ananian, The Car Doctor - March 14, 2026 - Hour 1 - When Your Mechanic Says Don’t Fix the Car
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The Truth About Diag, Flat Rate Pay, and Shop Culture with Josh Whiteman
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Ron Ananian, The Car Doctor - January 24, 2026 - Hour 2
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We're All Back Giving You Help With Car Repairs
Under The Hood show
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