94 LT1 Running Hot
Burning Brakes
Joined: Dec 2000
Posts: 1,161
Likes: 0
From: Orangeburg, NY
you may have dirt and debris between the condenser and radiator reducing the air flow. A simple solution is to pull the radiator. Remove the radiaator shroud, upper and lower radiaor hose, and two transmission lines (for automatic). don't worry about losing tranny fluid, only a small bit will come out. Pull the radiator and see what you find. While the radiator is out give it, and the a/c evaporator a good cleaning with simple green to get road grime off. After the units are cleaned put everything back together, using a 50-50 coolant mix. I am certain you will see a noticable difference. Running between 200-200 is normal. The fan goes on when the a/c is activated and/or the temp. hits 228.
Navigator
Joined: Jul 2006
Posts: 9
Likes: 0
From: Ventura CA
Running Hot
I have a 1993 with 116,000 miles on it. It started heating up last summer at one point to 247 degrees. I too read all the responses on the forum but the solution was the simplest to handle. Clean out the area between the radiator and the condensor. I had never done it so i thought what the hey, right.
It is not that difficult to do, there is a good sized hole looking from the passenger side into the space between the two radiators and stick a water hose or air hose for that matter and clean it out. You do have to get under the car to really see if you got it all out but I suspect you will be amazed at how much debris comes out of there.
I have not had a heating problem since...
It is not that difficult to do, there is a good sized hole looking from the passenger side into the space between the two radiators and stick a water hose or air hose for that matter and clean it out. You do have to get under the car to really see if you got it all out but I suspect you will be amazed at how much debris comes out of there.
I have not had a heating problem since...
Thread Starter
Intermediate
Joined: Jun 2006
Posts: 28
Likes: 0
From: Las Vegas NV
no leaves and pine straw here, maybe june bugs and dirt. being I reassembled from the firewall forward last winter, I did not think I could have clogged fins yet, but who knows. this car never really gets that dirty--
--but, radiator inspection time starts tomorrow.
--but, radiator inspection time starts tomorrow.
Drifting
Joined: Mar 2004
Posts: 1,500
Likes: 1
From: Mauldin sc
St. Jude Donor '05
no leaves and pine straw here, maybe june bugs and dirt. being I reassembled from the firewall forward last winter, I did not think I could have clogged fins yet, but who knows. this car never really gets that dirty-- --but, radiator inspection time starts tomorrow.
--but, radiator inspection time starts tomorrow. 
let us know what you find 
Race Director
Joined: Oct 2005
Posts: 11,771
Likes: 177
From: Rolla Missouri
2021 C4 of the Year - Unmodified Finalist
St. Jude Donor '10 thru '25
You can get it to run cooer, but you'll have to change the way the stock system came from the factory. Lots of members have done so. But there are also lots of opinions on the merits of it too.
Bottom line, If your cooling system is factory stock, then the cooling system operating temps. should be approx:
At idle no a/c: 225-235
At idle with a/c: 197-215
Moving at speed (over 35mph, A/C on or off): 190-197
So, 220 - 230 temps are causing no problems at all. Your car was designed to run in that range.
Intermediate
Joined: Aug 2006
Posts: 49
Likes: 0
From: Stuttgart
So, you don't want to accept the fact that running at 220 while idling at a stop light is normal?
You can get it to run cooer, but you'll have to change the way the stock system came from the factory. Lots of members have done so. But there are also lots of opinions on the merits of it too.
Bottom line, If your cooling system is factory stock, then the cooling system operating temps. should be approx:
At idle no a/c: 225-235
At idle with a/c: 197-215
Moving at speed (over 35mph, A/C on or off): 190-197
So, 220 - 230 temps are causing no problems at all. Your car was designed to run in that range.
You can get it to run cooer, but you'll have to change the way the stock system came from the factory. Lots of members have done so. But there are also lots of opinions on the merits of it too.
Bottom line, If your cooling system is factory stock, then the cooling system operating temps. should be approx:
At idle no a/c: 225-235
At idle with a/c: 197-215
Moving at speed (over 35mph, A/C on or off): 190-197
So, 220 - 230 temps are causing no problems at all. Your car was designed to run in that range.
I wonder if the dial gauge was in the middle for the exact same temperatures if people would be as concerned. And how much money third party companies have made because of this? Anyway I digress….
I have learned to trust the digital gauge instead of the dial gauge and it has never gone over 230 degrees. The moment it goes to 231 I will clean the radiator area!
Thread Starter
Intermediate
Joined: Jun 2006
Posts: 28
Likes: 0
From: Las Vegas NV
gentlemen, I can fully accept my car running at 220-230, as long as that is reality. 
If you look at the front of my C4, I have this huge airdam. it has basically blocked all but one direction of air and I am just wanting to make sure I have not hurt my car in the cooling in an attempt to direct air for handling. I know the op temps are normal from reading my factory manuals and all of the expertise here in the forum.
Experience is the ultimate reality.
I will be adding brake ducts to this dam, am now thinking of making it a "Y" duct--one side to radiator, one side to brakes, from both side of the dam. this car is being setup for silver state classic--last thing I need is overheating.
RollaMo-LT4; So, you don't want to accept the fact that running at 220 while idling at a stop light is normal?
If you look at the front of my C4, I have this huge airdam. it has basically blocked all but one direction of air and I am just wanting to make sure I have not hurt my car in the cooling in an attempt to direct air for handling. I know the op temps are normal from reading my factory manuals and all of the expertise here in the forum.
Experience is the ultimate reality.
I will be adding brake ducts to this dam, am now thinking of making it a "Y" duct--one side to radiator, one side to brakes, from both side of the dam. this car is being setup for silver state classic--last thing I need is overheating.
RollaMo-LT4; So, you don't want to accept the fact that running at 220 while idling at a stop light is normal?
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Racer
Joined: Dec 2004
Posts: 470
Likes: 0
From: Phoenix Arizona
OK, I searched posts for hours so I am just going to throw this out there 
My car, as pictured, runs on road for about 5 minutes on the road and the gage heads straight for 200'. Turning the defrost on brings it down a touch, but not much. I am a C3 head so this pressurized system is a new animal to me. I've told thermostat bad and all the horror stories. No leaks, no visible overheating, just runs hot--and it feels hot when I open hood too. Best I can tell the motor is stock, has 71k on it. And runs fine--just hot.
any suggestions would be appreciated.
My car, as pictured, runs on road for about 5 minutes on the road and the gage heads straight for 200'. Turning the defrost on brings it down a touch, but not much. I am a C3 head so this pressurized system is a new animal to me. I've told thermostat bad and all the horror stories. No leaks, no visible overheating, just runs hot--and it feels hot when I open hood too. Best I can tell the motor is stock, has 71k on it. And runs fine--just hot.
any suggestions would be appreciated.
Hope this helps
