I'm having problems that started recently. I have replaced the wires, plugs, cap, rotor, and fuel filter. All these actions have improved the response of the car but have not solved the overall problem. I have checked for trouble codes - none. There are no exhaust leaks. When the car is cold, sometimes takes time to start, and you can smell gas form the engine compartment. This I found odd because it is fuel injected. It also can hesitate before it revs up but when in gear will accelerate readily with sometimes a backfire from about the area of the cat but its peppy enough. BTW it is MPFI. The problem is once it warms up it will adjust the timing through the ECM and when you accellerate it will sputter and miss, back-firing until you back-off the pedal and try again where it will either go OK or do the same. It can also run fine if you apply steady slow acceleration. Then again it can react as if nothing is wrong and accelerate through the gears without a problem. When you are driving along at high speed it seems to run without problem, good acceleration and high end. At idle, running temperature, you can hear the engine change rpm's. When it is at a higher idle there is no miss and it rev's fine. At the lower rpm you get the hesitation in response to the throttle change. I am going to do the compression test on the cylinders next, but it seem to me that it would be constant through all circumstances if I had a flat lobe or sticking lifter. Any suggestions out there?
- posted
19 years ago