Below normal temp
Thread Starter
Drifting
Joined: May 2011
Posts: 1,542
Likes: 54
Below normal temp
Good morning friends, normally people post here about their coolant temp being too high and how that worries them. Well mine is the exact opposite.
Drove the car to work yesterday and had the low coolant light on briefly, did a quick check and found it to have sufficient coolant. But noticed that instead of it normal running temp of 193-200 it was running 183-190. Staying mostly in the 184 range. In traffic it would climb up as it normally does etc. I guess my main question is what would cause it to run cooler than it normally does? AC blows cold & heat blows hot. I added about 2 quarts of coolant into the overflow when I got home to be on safe side. 89 auto with no mods
Drove the car to work yesterday and had the low coolant light on briefly, did a quick check and found it to have sufficient coolant. But noticed that instead of it normal running temp of 193-200 it was running 183-190. Staying mostly in the 184 range. In traffic it would climb up as it normally does etc. I guess my main question is what would cause it to run cooler than it normally does? AC blows cold & heat blows hot. I added about 2 quarts of coolant into the overflow when I got home to be on safe side. 89 auto with no mods
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Fill and burp the radiator. You may have to repeat the service after the car sits overnite.
Then take it for a drive.
Then take it for a drive.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Coolant loss on any '89 should have you looking at #7 for symptoms of a leaking head gasket.
Scan for Coolant Temp Signal/Temp to see how it compares to the Display.
Thermostat needs coolant - not air - for it to work right so recheck once you've got a complete fill and no air in it.
Scan for Coolant Temp Signal/Temp to see how it compares to the Display.
Thermostat needs coolant - not air - for it to work right so recheck once you've got a complete fill and no air in it.
Thread Starter
Drifting
Joined: May 2011
Posts: 1,542
Likes: 54
going to try to burp it to make sure no air is in system then see how it runs. I replaced rad cap last year but that doesn't mean it hasn't gone bad. I also suspect that the thermostat might be stuck slightly opened even though heater blows hot (just a guess).
Thread Starter
Drifting
Joined: May 2011
Posts: 1,542
Likes: 54
seabright, you're explanation about the function of the thermo is absolutely correct (according to my research) & logical but I can't explain why now it runs at normal temp after I've replaced the thermostat. if the sensor was bad it would still show low temp. If it was due to lack of coolant then it would overheat. When it was stuck open, the car would get above 210 in traffic but once I was cruising it would go as low as 175 but once I changed the therm it now hangs around its normal 190-200 range. I'm perplexed but pleased that it is back to normal.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Melting Slicks
Joined: Aug 2008
Posts: 2,082
Likes: 50
From: Palmdale CA
Your Thermostat will Modulate when it's cool outside, and open more often as the outside temperature increase's. Eventually if it's warm enough outside the Stat will remain wide open...now you rely on the radiator/fans to keep the temps in reason.
Mine stuck in the winter one time, and I could not get above 150f and my heater Suffered greatly.
Mine stuck in the winter one time, and I could not get above 150f and my heater Suffered greatly.