relation between LTFT's and P0171, P0174
 

Hello All! Okay, I just moved from Albuquerque, NM (5500ft) to Sanford, NC (350ft). I keep getting P0171 and P0174 codes. They show up about every third/fourth day of running the engine, and they usually pop when the car is in steady state cruise. I have an UltraGauge scanner that I have set to monitor STFT's and LTFT's. The STFT's are usually between 0-5. The LTFT's, however, are around 15-20. I'm guessing the LTFT's are telling me that the computer is adding 15-20% more fuel to compensate, thereby triggering the P0171, P0174 codes. Correct??

The car is scheduled to go to a local shop for a data logging session on the dyno on Tuesday. I just can't sleep well wondering if I might have other issues?

The car has the following mods: Custom tune, Whipple, 3.75" pulley, LS9 camshaft, 1-7/8" LT's, full 3" exhaust, AlkyControl Methanol kit running smallest nozzle @100% Methanol (tune is not calibrated for the methanol, just running it for safety).

I have already checked for vacuum leaks as well. Thanks for any help,

Scott