I have recently baught my 94 Z28 and am new to this forum so please forgive any ignorance.

I have done some searching around but thaught it would be better if I posted my particular problem.

I was getting the from what I see usuall 1 - 2k miss/stumble/hesitation but then ran very strong through the rest of the RPMs

so I changed the wires. nothing

cleaned the MAF - nothing

changed the MAP sensor - nothing

pulled the vacuum on the egr and plugged the solenoid- nothing

Then after driving the car most of the morning I get back into the car and start it and it has this terrible miss..kinda like a dead cylinder. out of no where. Tremendous loss of power. so then

Changed the spark plugs - nothing

unplugged the MAF so it would use the default table - nothing

checked fuel pressure - OK

any one have any suggestions. I would hate to buy an Opti and still have the problem

 

Also I do not get an SES light

 

If you are missing in one cylinder, you need to find out which one. An easy way to do this is to unplug injectors one at a time and listen for the one that doesn't change the idle. Once you've identified the missing cylinder, you can try to troubleshoot that one.

A shot in the dark: check to see if a spark plug has backed out. I had one do that a while ago.

 

I tried that...the problem with that is sometimes you wil get a difference in idle...then on that same injector..you won't get a difference...kinda weird...

 

sounds like a classic opti stumble.