Hey guys let me say this is an awesome site as i just bought a 1 owner 87 5.7 iroc w/33000 km 20k roughly thing is it hasn't been drove or licenced since 97 as i got it from a good friend.The car has had a complete tune up ( cap,wires , plugs etc.)also an o2censor ,iac valve, 8 bosch 3 injectors,and the car is still running rich, when I was replacing the injectiors a mouse had chewed the air temp. wires only. No vacuum leaks and the cat delete, the car is driving me nuts, tried everything I can think of, VAC is 20lbs at idle, fuel psi holds 40 and with vac line off fpr47psi , car will change idle with MAF off,looking for any help plz. Don't know what to try next. I put the car on a dyno and it has 120 hp,sad I know the car has alot more go as I remember driving it when it was brand new and the car pulled hard, but now its not the case

 

Have you checked your compression? If it sat that long you might have some sticky valves or something causing low compression.

 

comp is 175 low 185high , found some chewed wires around the coil and harness , thx will report back.

 

Damn mice! If they got into the ECM wiring, that could be be part of the problem. I'd check the wiring harness to the ECM to eliminate that possibility. Those guys can get in tight places, you could have wiring issues just about anywhere.

 

were working on it now thx. report back

 

Your best bet would be to hook up a scanner and look at the data for the o2 to see whats its doing. If you see it stuck on 0 volts or .45 volts, I would be looking at the wiring from the pcm to the o2 sensor. How do you know that its running rich?