So I’ve been dealing with these codes for months, the lean code is causing the misfire code but the car barely misfires, it’s causing a very slightly rough idle and bad power output, and sometimes the car struggles to start the car is NOT running at 100%. I’m not sure what is causing this. The short term fuel trims bounce around -3 to 2-3% at idle but when I start driving it jumps up to 12%, for the long term fuel trims they sit at 20% at idle and drop down to 5-10% when I start driving. I’ve replaced the fuel filter, both O2 sensors, and cleaned the MAF sensor. I think it’s either the fuel pump or a vacuum leak, I’ve sprayed all the vacuum lines and places with probable leaks with carburetor cleaner to see if I could find a leak and had no luck. Does anybody know what else could be going on or how I could test to see whether it’s for sure the fuel pump or a vacuum leak? Also the mods on the car are #60 Siemens injector, smaller supercharger pulley, zzp upgraded coils, upgraded radiator and heat exchanger, zzp cold air intake, zzp shorty header and zzp 2.5 catback exhaust, pretty sure it’s the zzp stage 3 kit. Other problems with the car that I don’t think have to do anything with the problem but I don’t know is the AC compressor clutch doesn’t work, the air door actuator motor makes a loud ticking sound and that’s about it please if anyone could help it’d be greatly appreciated!!!!!

 

Did you ever figure out ?