cool my vette
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2nd Gear
Joined: Nov 2006
Posts: 2
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cool my vette
I have a 1993. It has 9242 miles on it. I want to sell it but noone wants to buy a car that has a cooling problem. With the engine on and the a/c on the primary fan will come on, however, with the car running and the a/c off neither fan will commit even when the temp reaches near the red zone. It was really embarrassing to have to have my car towed home while a ford mustang was sitting next to me laughing. Please help
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
I rarely even rely on the analog guages. The analog gets it's reading from a sender in the head. The digital gets its signal from the CTS in the waterpump. I usually watch my digital guage and don't get worried until the temp gets 240*+.
I spent about 45 minutes observing the coolant temperature operation range on my stock (never modified) 95 LT1 with 50,000 miles...180* stat. I started the engine and let the temp rise. All of the info is while at idle and the outside temp 80*. Idle temp reached 228* before both fans came on and never saw the temp past 230* via digital guage. Analog guage was in the hash marks and showed approx. 250* from guessing, 260* being the highest number which is miss leading. The temp dropped to 217* and both fans cut off. With the A/C on the temps sat around 201-205* and never got lower or higher. This I consider normal at idle and when driving at about 55 mph the digital temp guage stays around 185-190* range.
Check between the A/C condenser for trash (bird nests, leaves, plastic bags, anything that will block air flow to the fins). Make sure the air is out of the coolant system as temps will stay on the hot side due to air pockets. Make sure the coolant level is full and there are no leaks in the system. Make sure the fan(s) are operating as they should.
Check between the A/C condenser for trash (bird nests, leaves, plastic bags, anything that will block air flow to the fins). Make sure the air is out of the coolant system as temps will stay on the hot side due to air pockets. Make sure the coolant level is full and there are no leaks in the system. Make sure the fan(s) are operating as they should.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
You probably have a cooling temp sensor that's bad. The temp sensor is used as input to the ECM which controls the fan operation depending on the temp it sees. The secondary fan relay may not be working either if it does not run at all. You can also apply 12v directly to the wire going to the fan to check for operation.
With the engine running and the A/C turned on, both the primary and secondary fans should be running. Also, jumping pins A and B in the ALDL will force both fans to run with the ignition switch turned to the ON position (engine not stated).
The digital temp display is the more accurate one and the display value you see is what the ECM uses to turn on the fans. The primary fan will come on at about 228 degrees and shut off when the temp drops 36 degrees. The secondary fan comes on at around 238 and shuts off when temp drops 36 degrees. Both fans will remain running with the A/C on.
With the engine running and the A/C turned on, both the primary and secondary fans should be running. Also, jumping pins A and B in the ALDL will force both fans to run with the ignition switch turned to the ON position (engine not stated).
The digital temp display is the more accurate one and the display value you see is what the ECM uses to turn on the fans. The primary fan will come on at about 228 degrees and shut off when the temp drops 36 degrees. The secondary fan comes on at around 238 and shuts off when temp drops 36 degrees. Both fans will remain running with the A/C on.
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
Originally Posted by bartend08
I have a 1993. It has 9242 miles on it. I want to sell it but noone wants to buy a car that has a cooling problem. With the engine on and the a/c on the primary fan will come on, however, with the car running and the a/c off neither fan will commit even when the temp reaches near the red zone. It was really embarrassing to have to have my car towed home while a ford mustang was sitting next to me laughing. Please help
Drifting
Joined: Apr 2005
Posts: 1,283
Likes: 12
From: New York
Originally Posted by bartend08
I have a 1993. It has 9242 miles on it. I want to sell it but noone wants to buy a car that has a cooling problem. With the engine on and the a/c on the primary fan will come on, however, with the car running and the a/c off neither fan will commit even when the temp reaches near the red zone. It was really embarrassing to have to have my car towed home while a ford mustang was sitting next to me laughing. Please help
Instructor
Joined: Apr 2006
Posts: 108
Likes: 0
From: Green Cove Springs Florida
I installed a 160 degree thermostat in my 95 and programmed it to turn on at 195 and off at 185. It now runs on the road at a little less than 185 and sometime when not moving and in traffic it will get to around 200 in Florida's heat. With air conditioner on it hovers around 185. It used to run up to 260 all the time when in stop & go traffic. I feel much better seeing it setting around 185 than 250 or better. I can't beleive running that hot is good for the engine.
Cmanhome, in Green Cove Springs, Florida
Cmanhome, in Green Cove Springs, Florida
