High Idle and check engine light glowing

After a new water pump and thermostat installation, I have an elevated idle (1000 rpms without touching gas pedal) and a check engine light that comes on after 82 Vette warms up.Could this be due to a vaccum leak?

Did you replace the 160 degree thermostat with the correct 190 degree thermostat?

I replaced it with a new 195? thermostat. This is the degree of my original thermostat that seemed to never show check engine and high idle. So to recap, I replaced a 26 year old 195 ? with a 180 ? (I was wrong when I first thought that my mech. installed a new 160?) and finally back to a new 195? ). I noticed that the valve of the old 195? was easy to push open with my fingers, but the new 195? was almost impossible to push open with my fingers. Thank you for showing interest in my problem. Bob

I was hoping it was just the thermostat. I have a 93 Caprice with TBI and the folk on this Yahoo group for TBI have been helpful in the past. Are you having the same problems with the new 195 degree thermostat? Hopefully some of the more experienced forum members can chime in.


Just a thought, it’s better to post the follow up in the original thread rather than starting a new one. This way the forum members know the entire story and can adjust their comments accordingly.

Good luck,

Ed B.

That CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code (like P0123) not just their translation into English and post it back here.

Vacuum leaks can cause problems that dont set codes, so I would not concentrate on a vacuum leak for the cause of your "check engine " light.

Better a glowing check engine light than a glowing engine.

Will do tomorrow. Thanks. Bob

Autozone, Advance Auto etc. are not likely to be able to interpret the codes on an '82 Corvette with–I assume–an OBD I system. The codes are completely different from the P0123 format on these old systems.