Cooling trouble with my 94. 5.0 Please Help
 

I bought a 94 gt convertable about a year ago. It always ran more warmer than normal. It was rebuilt before I bought the car. It is not stock. Anyway, I have changed the block, got the heads pressure tested, changed the waterpump three times, got the radiator checked, new hoses, THE HEAD GASKETS ARE ON CORRECT, new thermastat. The car will run at about 180 deg. for about ten min., then the temp keeps climbing. I am at the end of my rope. In need of help.

replace the coolant temperature sensor.

System have correct and working radiator cap? does the fan work correctly on both High and Low speed? you ever do a coolant flush on this car? to much timing/to little fuel can make a motor run hotter then normal as well.

Does the upper radiator hose get hot when the car is warmed up?

LOL I forgot the first question you always ask.

I had an issue like that and turns out someone installed the wrong temp sensor.

I went through a similar bout with my '67 years ago. Ended up being a radiator cap. That being said, I've heard that the '94/'95 fan relays are a little sketchy (I have a '95 that's been OK so far)

I've got a 96(v6) and on a warm day in stop and go traffic mine will get really hot if I'm not running my a/c. I don't think my fan works in low speed. How do u test that? BTW, how does a radiator cap cause u to run hot? Loss of coolant?

I am not 100% on how to check for a bum relay on the 94/95 but I would think you get it to where the fan should be on (in this case, hot day / no AC) and test for voltage on both sides of the relay in question. If no voltage in, then lean towards temp sensor, if no voltage out, then prolly relay. put a jumper in to seeif fan kicks on... def relay? Probably over simplified it but I'm guessing.

As far as the rad cap, a liquid's boiling point increases when it is under pressure. Our rad cap creates a pressurized environment where the boiling point of the coolant is raised and can be kept as a liquid at a higher temp. If the cap can't hold the pressure, then the boiling temperature is lower and once the liquid boils - it expands and tries to turn into a gas, it cannot effectively cool like it's supposed to as a gas...so it snowballs and gets hotter, and boils more, and gets even hotter...... until something gives (usually a warped head and blown head gasket as it's spraying steam from your radiator cap)

i know this is the 5.0 thread and i have a v6 but anyone know what the difference is in the colors on the temperature switch. i got one from autozone when i first got my car and there was a green one and a red one. i just got the same color i had and i asked the autozone guy what the difference was-he could not tell me. maybe it is a different temperature rating and i had the wrong one on my car so i bought the wrong one. maybe the other one would kick my fan on a lot sooner. anyone know for sure?

If the low speed is not working could be CCRM. Just do a google search and you will pull up alot on it.

That's what I was trying to come up with.. couldn't remember what the deal was