overheating
germana
11-05-2007, 11:50 AM
I have an issue that I can not resolve on my 99 caddy STS. It overheats at speeds above 40mph. I have replaced the water pump twice, radiator tensioner, radiator , overflow tank cap. belt and thermostat twice, but it continues to overheat. I have had the system flushed and refilled with fresh antifreeze.If I am driving and it overheats, I just reduce speed to idle engine or pull over and it cools down in about 2 minutes, Both cooling fans work. Any and all suggestions would be appriciated
caddydaddy
11-05-2007, 08:40 PM
Check to make sure the cooling fans are working. I had one fail on my 2000 STS. I'd also have the cooling system tested for possible leaking head gasket. You can test it yourself with a kit from NAPA for about $50.
4pt9fiero
12-15-2007, 10:47 PM
If it is only overheating at speed it could be that the radiator hose is collapsing. I have seen this problem before in a pickup truck I owned. Replaced a lot of stuff, radiator, waterpump, thermostat - turned out to be a $10 hose.
Good luck
Good luck
zyzzle
03-18-2008, 08:51 AM
Sounds like a headgasket leak or possibly a cracked head. I have an issue that I can not resolve on my 99 caddy STS. It overheats at speeds above 40mph. I have replaced the water pump twice, radiator tensioner, radiator , overflow tank cap. belt and thermostat twice, but it continues to overheat. I have had the system flushed and refilled with fresh antifreeze.If I am driving and it overheats, I just reduce speed to idle engine or pull over and it cools down in about 2 minutes, Both cooling fans work. Any and all suggestions would be appriciated
95kat
08-20-2008, 07:00 PM
Hi All,
I had the same problem with my 1994 STS. On the Drivers side right above the water pump there is a 3/8 hollow bolt with a rubber hose attached to it. take the rubber hose off and start the engine. If antifreeze comes out of the bolt then you might have head gasket problems. If nothing comes out of the bolt, take the bolt out and make sure it is not clogged. If it is not clogged take off the top engine cover. There is a metal line that runs under the front of the engine cover and is attached to the tank and the water pump, also may be clogged. In my case my bolt was clogged with pieces from my hose which was stopping antifreeze from flowing to the water pump. I had to find out the hard way. i changed water pump, tensioner, radiator, and heater core. The end result was a stupid clogged bolt. Before you perform these procedures, make sure the tank is full. If you have to take the top cover off to inspect the metal line, DO NOT START YOUR CAR WITH THE TOP COVER OFF. If you do the engine will rev to red line Hope this helps
I had the same problem with my 1994 STS. On the Drivers side right above the water pump there is a 3/8 hollow bolt with a rubber hose attached to it. take the rubber hose off and start the engine. If antifreeze comes out of the bolt then you might have head gasket problems. If nothing comes out of the bolt, take the bolt out and make sure it is not clogged. If it is not clogged take off the top engine cover. There is a metal line that runs under the front of the engine cover and is attached to the tank and the water pump, also may be clogged. In my case my bolt was clogged with pieces from my hose which was stopping antifreeze from flowing to the water pump. I had to find out the hard way. i changed water pump, tensioner, radiator, and heater core. The end result was a stupid clogged bolt. Before you perform these procedures, make sure the tank is full. If you have to take the top cover off to inspect the metal line, DO NOT START YOUR CAR WITH THE TOP COVER OFF. If you do the engine will rev to red line Hope this helps
95kat
08-20-2008, 07:01 PM
Hi All,
I had the same problem with my 1994 STS. On the Drivers side right above the water pump there is a 3/8 hollow bolt with a rubber hose attached to it. take the rubber hose off and start the engine. If antifreeze comes out of the bolt then you might have head gasket problems. If nothing comes out of the bolt, take the bolt out and make sure it is not clogged. If it is not clogged take off the top engine cover. There is a metal line that runs under the front of the engine cover and is attached to the tank and the water pump, also may be clogged. In my case my bolt was clogged with pieces from my hose which was stopping antifreeze from flowing to the water pump. I had to find out the hard way. i changed water pump, tensioner, radiator, and heater core. The end result was a stupid clogged bolt. Before you perform these procedures, make sure the tank is full. If you have to take the top cover off to inspect the metal line, DO NOT START YOUR CAR WITH THE TOP COVER OFF. If you do the engine will rev to red line Hope this helps
I had the same problem with my 1994 STS. On the Drivers side right above the water pump there is a 3/8 hollow bolt with a rubber hose attached to it. take the rubber hose off and start the engine. If antifreeze comes out of the bolt then you might have head gasket problems. If nothing comes out of the bolt, take the bolt out and make sure it is not clogged. If it is not clogged take off the top engine cover. There is a metal line that runs under the front of the engine cover and is attached to the tank and the water pump, also may be clogged. In my case my bolt was clogged with pieces from my hose which was stopping antifreeze from flowing to the water pump. I had to find out the hard way. i changed water pump, tensioner, radiator, and heater core. The end result was a stupid clogged bolt. Before you perform these procedures, make sure the tank is full. If you have to take the top cover off to inspect the metal line, DO NOT START YOUR CAR WITH THE TOP COVER OFF. If you do the engine will rev to red line Hope this helps
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