Mechanics

CHEVY POOR PERFORMANCE WHEN WARMED-UP

1985 Chevrolet Corvette

Engine Performance problem
1985 Chevy Corvette V8 Two Wheel Drive Manual 30,000 miles

" 85 vette has all kinds of power when cold but as she reaches normal operating temp. She developes a " miss" and power drops off to the point where I think I'm driving a 6 cyl.
When I had the car safetied they said it needed a EGR valve.
Could this lead to such poor performance?
I've replaced cap, rotor, wires and coil.
seems to run hot too. Around 110 deg. C. In summer. The fan runs almost continually and I've noticed that after sitting overnight, when I start up it will puff some blue smoke.
Please help!
Steve
Avatar
Steven.terry@gi-de.com
September 14, 2008.



The blue smoke is most likely bad valve seals, they leak while its cold into the cylinders. I would definitely suggest replacing your pcv to begin with. The pcv allows the crankcase to ventilate, without ventilation seals with blow. The oil leaking into the cylinders, then into the exhaust is probably the reason your egr went bad. The egr valve will only affect the computer when the engine coolant temp has reached 176 deg F

As for running hot that could be a number of issues, begin cheap and go to the more expensive stuff(thermostat, coolant temp switches, then water pump) WHATEVER you do, DO NOT remove the thermostat and run it. GM engineers worked hard to make the corvette temp stay right about 205 deg F, thats why your fans run nearly constantly.

I hope this helps.

Tiny
TurnedWrench
Sep 16, 2008.
Thanks for your input.
I suspected the valve guides as well.
I'm going to make sure the EGR is working first.
Trouble is there is so many things in the way on this car but with this hood, work is easy.