I bought this 2000 Suburban a couple months ago. The guy selling it gave me a great deal, as the truck was vandalized, and needs a good amount of deep scratch repair work done, which I'm in the process of doing. In the mean time, It took the truck in till get it smoged, and just my luck! It failed smog. Technically, it wasn't "ready" as the on board system hadn't fully run its own diagnostic to give a reading, since the battery had been drained down while sitting before I bought it. I drove the truck around a while and instead of my problem disappearing, it grew. Check engine light came on. A scan showed pending codes of00D9,P3200,P0300 and confirmed codes of: P0134,P154, Here's a list of what I have done since getting the truck: wheels and tires, Wheel hub bearings, Radiator flush/new coolant, Engine and trans Oil/Filters, plugs and wires, intake air filter, cabin air filter, head lights, oxygen sensors, fuel filter, cleaned throttle body, new gas cap, Re-flashed ECM. Today, I drove around maybe 5-8 miles, being very easy on the drive, and no light. It seems to come on during heavy acceleration, at around 55 mph, or if sitting in park and revving at 3000-3500 RPM. Any ideas on what could be causing the check engine light? The muffler has a small leak it looks like, but I ordered a flowmaster replacement already. I just need this truck to pass smog, but I'm not really looking for a band-aid to get through the smog test(rubbing alcohol, idling engine for hours before the test). Thanks. Note: My traction control is stuck in "off", ABS light stuck on (replaced wheel hubs that were causing tai-fighter sound, so fixed the sound, but light still on?), I can not turn on my towing assistance with the shifter, the oil pressure gauge jumps around when idling, from around 40 to 48 psi. Then it will flat hit 80 while accelerating, especially on the highway. It seems to run cold, as it takes a while to warm up, and never actually gets up past 185. It seems to have a strong motor and the transmission is not slipping, but it does seem to have a lag, where if I don't let it catch up before making any passing moves, it will struggle to pass, after a moment of lag, sometimes even throwing into too low of a gear it seems like as I'll almost get thrown forward before I get a response from the gas pedal. Again, regardless of suggestions, I'm already planning to replace the muffler, but I'm contemplating coolant temp sensor, injectors, coil packs, vacuum solenoid, vacuum lines, EGR/gasket, intake manifold gasket. Any pointing in the possibly right direction would be appreciated, thanks again.