I've replaced almost every component that has to do with fuel/exhaust system to try and fix this problem. Mass air flow sensor. Oxygen sensors. Fuel pressure regulator. Fuel pump. Fuel filter. Spark plugs and wires. Cap and rotor. IAC valve. MAP sensor. Ignition coil. Still had codes and running...

Ok. I have 2000 Chevy c2500 RWD. Last year service engine soon light came on. Started running lean. Rough idle. Hard start. I changed the o2 sensors. All of them. Same thing. Changed fuel pump. Same thing. Replaced TPS. Same thing. Spark plugs and wires. No results. Ignition coil. Same...

I have a 2000 chevy c2500 obs 5.7liter. I've been running lean for a while and I don't know how to fix it. I've replaced all o2 sensors, fuel pump, fuel pressure regulator, throttle position sensor, mass air flow sensor, and still running lean. Vacuum? It's possible but I did a compression...