87irocker

I have an 87 Iroc 5.7L TPI, Auto which has been in storage for almost 2 years. 57,000 original miles on this, runs very strong and was been well maintained by original owner. When I put it away 2 years back (garaged) it was running perfect. When I started it last week it idled rough and would hesitate then run really rough / no power until about 3500 rpm where it would start to even out.. runs a little better when warm but this is not like the car I put into storage...

List of concerns:

1) bad gas / clogged injectors - gas I started it with is now 20 months old, I topped of tank, added fuel injection cleaner stuff, not really running better.... changed fuel filter... no better (it was clean)

2) wires - checked wires, changed plugs... wires were new a month before it went away

3) mice - seriously... someone told me that mice could have built a nest somewhere so I check the intake, exhaust... but have found nothing...

4) fresh fluids - changed oil and filter; what came out was pristine (car has been on mobile one since it was born and oil changed every 2000 miles)

5) electrical - i did a visual inspection and harness and wires look fine

I have it in 2nd shop today but this and last mechanic admit they "don't really know too much about these engines" although this one will scan for codes (check engine light is NOT coming on)

Note: has hi-performance chip (could this fail intermitently?), a few minor mods like airfoil, K&N filter etc

Any ideas would be appreciated or recommend a should west / southwest of boston, ma (near foxboro patriots stadium).
--
Dave

PS: also remember a few other mods, 170 degree thermostat, flowmaster.

Big Dave

OK, first off, if a shop actually told me they "didn't know too much about these engines", I would not even let them touch it.

Sounds to me like a fuel issue, especially if you know the gas is old. Ideally, you should have drained it, purged the lines, and put in fresh gas. But diluting the old gas is ok if there was little in the tank to begin with and you filled it up with fresh. The injector cleaner also a decent idea. How much has it been run/driven since coming out of storage?

Is also possible you've got an injector or two not firing. They can and do get stuck.

Dave

87irocker

I mixed 1/2 tank old with 1/2 tank new - agree that i should have drained it all out so will give that a try to help troubleshoot. I interesting thing is that it does not seem to be skipping just no power which made me wonder if it could be a fuel / air starvation issue.

afida15

drain the gas and put a can a sea foam in it with 8 gallons of gas.