1994 GMC C1500 V8 Four Wheel Drive Automatic 183924 miles
My 1994 GMC sierra SLE z71 has been having a few problems lately, when I rev the engine when it is warmed up it emits black smoke and when I start it I get a blue smoke from the right hand side of the engine (it has dual exhaust), I also get a egr trouble code every once and a while. I have also been getting poor mileage when a few months ago I was getting 14 in town and 17 on the highway (not bad for a 4x4 with 33 inch mud tires). The engine has headers, a cold air intake, a throttle body spacer and the throttle body has been smoothed out. It has a new distributor cap, rotor, accel super stock wires, AC Delco plugs gapped at 0.35 and an MSD blaster coil. There is also a motorvation chip in it. THere is a new fuel pump, tank, IAC, TPS, MAP, O2, EGR control, temperature sensor, all have been replaced over the course of a year and a half. I made my own adjustable fuel pressure regulator but did not change the diaphram. What to you suggest that the problem could be?
Monday, February 18th, 2008 AT 11:16 PM