Coolant Temp.
Thread Starter
4th Gear
Joined: Dec 2011
Posts: 4
Likes: 0
Coolant Temp.
I just purchased my first Corvette, a 2002 convertible (6 speed), and am new to this forum. Over Thanksgiving, the coolant reservoir tank developed a leak. I purchased and installed a new tank, and followed the procedure for adding Dex-Cool. The engine temp. now stays in the 160 - 170 range unless I keep the rpms over 3000. Since I replaced the tank, I have received the P0128 code twice. Any ideas on how to fix this issue would be greatly appreciated.
Pro
Joined: Aug 2010
Posts: 593
Likes: 9
From: San Antonio Texas
There is a procedure for "burping" the cooling system that you can look up on this forum. Usually when there is an air lock in the system you get overheating but it is easy enough to do and worth a try. This is a pressurized system and needs a bit of care when replacing fluid. Sorry, I did not look up the 0128 code. What does it signify?
Thread Starter
4th Gear
Joined: Dec 2011
Posts: 4
Likes: 0
The P0128 code appears to mean that the engine's PCM detected that the engine has not reached the required temperature level within a specified amount of time after starting the engine. The intent of the P0128 code is to indicate a faulty thermostat. Similar codes: P0125
In determining the engine did not reach a "normal" temperature, it takes into account the length of time the vehicle has been running, the intake air temperature (IAT) sensor reading, the engine coolant temperature (ECT) sensor reading, and the speed of the vehicle.
Looks like I may be replacing the thermostat.
In determining the engine did not reach a "normal" temperature, it takes into account the length of time the vehicle has been running, the intake air temperature (IAT) sensor reading, the engine coolant temperature (ECT) sensor reading, and the speed of the vehicle.
Looks like I may be replacing the thermostat.
Pro
Joined: Aug 2010
Posts: 593
Likes: 9
From: San Antonio Texas
I would burp the system first. You can easily check the operation of your T stat by removing it and putting it in a pan of water and bring it up towards boiling. Watch to see when it opens with a thermometer in the water. It sounds like it is stuck open to me. There is a procedure for replacing the T stat that does not require you to drain the system and you only lose about a half pint of coolant. Do a search on that as well! Wish I could be more help. Good Luck.
Race Director
Joined: Jan 2007
Posts: 18,643
Likes: 14
From: Norman Oklahoma - The Only State in the Union with no Blue Counties!
I would burp the system first. You can easily check the operation of your T stat by removing it and putting it in a pan of water and bring it up towards boiling. Watch to see when it opens with a thermometer in the water. It sounds like it is stuck open to me. There is a procedure for replacing the T stat that does not require you to drain the system and you only lose about a half pint of coolant. Do a search on that as well! Wish I could be more help. Good Luck.
Burp and swap out the stat with a 160. I wouldn't even bother testing the old one.my $00.02
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
2027 Corvette vs The World: Every Model vs Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
10 Things C8 Corvette Owners Hate (But Won't Tell You)
Joe Kucinski
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!
Brett Foote
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)
Joe Kucinski
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!
Michael S. Palmer
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!
Joe Kucinski
Drifting
Joined: Apr 2007
Posts: 1,760
Likes: 4
From: Broward County Florida
I replaced my tank a few months ago and everything was fine. Just last night on my way home from work my temp gauge pegged redline and then quickly went back down. I thought it might have been a malfunctioning sensor (like the oil pressure gauge issue) but when I got home and looked under the hood, I saw the fill tank was empty. I checked the motor this morning (cold) and the coolant never filled back into the tank.
I must have a leak somewhere? Any ideas where I might begin looking? I didn't see anything obvious. No spillage under the car, no odd smells, touched all the hoses and they seem to be okay...
This morning I filled up the tank and kept the fill cap off to burp it and then secured it tightly. :
:
I must have a leak somewhere? Any ideas where I might begin looking? I didn't see anything obvious. No spillage under the car, no odd smells, touched all the hoses and they seem to be okay...
This morning I filled up the tank and kept the fill cap off to burp it and then secured it tightly. :
:
Le Mans Master
Joined: Dec 2000
Posts: 5,245
Likes: 25
From: Blue Ridge Georgia
Start w/ a cold engine
Remove rad. cap
Idle for 1 minute
Install cap
Cycle RPM from idle to 3000 until coolant reaches 210F
Shut off engine
Remove cap
Start engine
Idle for 1 minute
Install cap
Cycle RPM from idle to 3000 until coolant reaches 210F
Shut off engine
Remove cap
Top off
Remove rad. cap
Idle for 1 minute
Install cap
Cycle RPM from idle to 3000 until coolant reaches 210F
Shut off engine
Remove cap
Start engine
Idle for 1 minute
Install cap
Cycle RPM from idle to 3000 until coolant reaches 210F
Shut off engine
Remove cap
Top off
Melting Slicks
Joined: Jun 2010
Posts: 2,809
Likes: 3
From: Yorktown Virginia
I may be mistaken but if he had an air bubble in the system wouldnt he be seeing high temperatures... and if he is wanting the temp to reach operating range in the time it should why would he put in a 160 t stat and not a factory. The 160 is not going to do him any good with helping the temp get up to 190, yes both the factory one and the 160 will be wide open at that time but it is going to take much longer for the 160 to reach 190 at it is wide open at 160.
It sounds like either the previous owner installed a 160 t stat or yours is broke and stuck open, if you replace it with a factory one you should see your temperatures in the normal operating range.
It sounds like either the previous owner installed a 160 t stat or yours is broke and stuck open, if you replace it with a factory one you should see your temperatures in the normal operating range.
