Fuel Trim Malfunction (P0170) Empowering You with the Knowledge to Resolve It

Well-Known Member ... The P0170 is based upon a rich mixture that the PCM is trying to lean out when it reached the end of its lean range. Perhaps ... A code P0170 means that the PCM is either subtracting too much fuel and making the mixture too lean, or it's adding too much fuel to make the mixture too rich. P0170 means there was a malfunction in the computer's control of the air:fuel ratio. It also indicates that the fuel trims reached their limit of adding fuel. After many enquiries I was told everything from O2 Sensors, Vacuum Leaks, Injector Problems, Fuel Pump Problems, Faulty MAF and Catalysts. Pull the vac line off the fuel pressure regulator and see if any gas drips out ... this means a bad regulator and will cause trim code.. You're after cat lambda is showing a lean condition +16% this is the LTFT but the Short trim ( stft ) is in the range 2.3%. Googling gives me P0170 Fuel Trim Malfunction (Bank 1) - fuel trim malfunction. It does have a rough idle but has not stalled. I've gone through ... This thing comes and goes on me time to time with weird idle supposingly it happens if you put to much gas in the car or don't lock the gascap properly. My 97 lude is throwing P0172 that reads "System running rich" and P0170 reads"fuel trim malfuntion". What does those codes mean? How can i fix it? hi. I have just joined the club and I need to no how to fix a error code p0170 fuel trim bank 1 problem . I have change the 2 lamba sensors ...