hello
i have a problem with my 94 that is puzzling me.
6speed 140k miles no ses light service ride control (z07 option) light is on, but that is a bad servo that i know about no other indicators on new battery alternator normal output all other temp indicators in normal rangesthe symptoms started a few months ago. in top gear at high way speeds, it will seem to miss when a demand is placed on the engine (going up a hill, passing, etc). in the ensuing months, it seems to have gotten worse, in that it now:
at idle (which used to be around 800rpm), it would start to hunt, going from
800-2000, with no throttle input. during around town driving, say in 4th at 45, the engine would speed up so the car would accelerate, with no throttle changes being done by me. the pedal doesn't move under my foot, so it's not a spring, i believe.i replaced the iac valve and airfilter at this point. when the old one iac was removed, it had a lot of crud on it. i cleaned out the opening to the throttlebody, but didn't take it off for a complete cleaning. i also replaced the water temp sensor, as i noticed the harness connector was cracked.
the problem has now changed, in that the idle has dropped to an abnormal low of 400 and seems to almost stall. it still has the missing and bucking at constant speeds, and also misses pulling away from a stop.
i took it to my local mechanic, whom i've had for about 20 years. he noticed that every time it surges, the service ride control light changes intensity. he seems to feel that the computer is bad and is affecting the timing somehow, and said i should take it to the chevy dealer.
could this be a fuel delivery problem (fuel pump, filter, bad injectors)?
are there any other sensors that this could be, or does this sound familiar, and if so, are there tests for them so i don't have to start throwing expensive parts at the problem?
thanks, charlie cave creek, az