Any help is much appredciated,
I have a 96 GMC Jimmy, it is hard to start. It has black smoke out tail pipe. It backfires. It has a bad smell of gas out the tail pipe. It runs horribly. The computer only reads one code, Multiple cylinder Missfire. and also gives me data. That My IGNITION ADVANCE IS: - 24, What does that mean? is my timing off? the Jimmy has 240,000 miles, i would suspect that the timing chain might be worn. I have replaced the following, The fuel regulator, and cleaned the spider. I replaced the plugs, wires, cap , rotor, new map sensor, new maf sensor. I cleaned the EGR valve. I believe that the computer has also put the transmsiion into "limp home mode" because it had all the gears but now, is only in second. Does anyone know as well, on the ECU there are three plugs that should be plugged in or two. Mine has a place for three plugs. and the center one was unpluged i just plugged it in, didnt change anhything????? ANyways ANBODY HAVE ANY IDEAS ??? Thanks SO MUCH Cory-
