Question2000 MITSUBISHI GALANT ES 2.4L AUTO
MY CHECK ENGINE LIGHT CAME ON & I WENT & HAD AN DIAGNOSTIC TEST DONE.
THE CODE CAME UP PO 170 FUEL TRIM MALFUNCTION.
WHAT EXACTLY IS THAT TELLING ME BECAUSE, THE MECHANIC DOSEN'T REALLY KNOW.
AnswerDonte,
First, get a new mechanic. If they can pull a code from your car's computer (ECU), they should be able to tell you what it means.
The fuel trim basically is the level your ECU sets your air-to-fuel (A/F) mixture at. If your engine is getting more fuel than your ECU wants, or if your engine is getting more air than the ECU wants, your check engine light can come on, and throw the general P0170 (Fuel Trim) code.
In general, an out-of-spec value can indicate a vacuum leak since it is mostly present at idle, when vacuum is highest. An out-of-spec value can also indicate a fault at higher RPM, and may point to a faulty mass air filter (MAF) sensor. A dead or slow O2 sensor will also cause problems with your fuel trims.
I'd recommend finding a mechanic that will check your O2 sensor, your mass air sensor, and also perform a vacuum check on your system to find any possible air leaks.
Good luck!
