I installed a custom tune on my car a few days back and threw a code the other day a p0174 code. Its a lean bank 2 code and was told to check for vac leaks, exhaust manifold leaks, headgasket problems...etc. Anyone run into this problem? I dont seem to have a vac leak, I have checked over everything
Tuning lean condition
- Thread starter hotrodjcc
- Start date
First you need to confirm if it's a real or false condition. If you don't have a wideband or something you might try swapping the O2s. Log MAF, fuel pressure, and battery volts and see if either of them suddenly drop or flatline during a moderate pull, and see what fuel trims are up to.
In the meantime don't abuse it or give it boost until you know for sure.
If everything checks out and it's the tune itself, you can add global fuel to the tune, but if your tune is that bad to begin with I would go back to stock (since you don't have a pulley/MAF/injectors) and seriously consider another tune.
Unlikely that it's a gasket or something if it started right after you installed the tune; the light doesn't come on right away, it takes a few cycles and attempting to compensate before it finally gives up and trips the light.
In the meantime don't abuse it or give it boost until you know for sure.
If everything checks out and it's the tune itself, you can add global fuel to the tune, but if your tune is that bad to begin with I would go back to stock (since you don't have a pulley/MAF/injectors) and seriously consider another tune.
Unlikely that it's a gasket or something if it started right after you installed the tune; the light doesn't come on right away, it takes a few cycles and attempting to compensate before it finally gives up and trips the light.
Well I reset the PCM after the tune was installed. I ran a data log and even the tuner said there was a 20% variation between the 2 banks and told me these possibilites. I thought about returning the car to the stock tune and data logging it to see if it is still the same readings
When you say he told you a 20% variation are you speaking of STFT at idle or LTFT while logging (a 4th gear pull). Do you have a AF in the car? you could have a bad 02 or a injector going south. You need to get into this before pounding on the car so you do not hurt it.
Well think about it this way... you had no problems before flashing right? Since you are basically stock, go back to the stock tune and watch the fuel trims and confirm there is real problem.
The last guy that had a problem with this on this site, it turned out to be the MAF+Mafia... still curious how a single common air meter can cause only ONE bank to load up...
The last guy that had a problem with this on this site, it turned out to be the MAF+Mafia... still curious how a single common air meter can cause only ONE bank to load up...
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I tuned it back to stock and seems to be ok besdes the Cat code from my o/r pipe. That does seems strange how a MAF will cause one bank to have issues. I am thinking about swapping out my upstream o2s cause I've read they can get lazy in reading with heater wire problems.
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