I have a 02 WRX it keeps throwing the code p0171 so far I've checked for vacuum leaks, I've cleaned my MAF sensor, I changed my O2 sensor like 4 months ago what else could it be? I'm probably gonna check my fuel pressure tomorrow could it be due to my tune? I'm running a OTS stage 2 map. My current mods are TBE, catless up pipe, turbo xs tmic, 3 port ebcs, intake, P&P heads +1mm valves. I have been running this OTS MAP with no problem for a little over a month now so not entirely sure if its to do with the tune or something else?