If the car going into the red? If it isn't then it isn't overheating. Let the car idle and see if it travels above 240. I sound like a broken record.

The A/C has a low pressure cutoff switch and the compressor won't engage if there isn't enough refrigerant in the system. If your A/C isn't charged or if you don't normally have A/C then the fans will not automatically turn on.

 

Yes, my car will and has got into the red, the fans never kick on and the car gets so hot it throws the coolant into the overflow tank.


So the thing I'm trying to figure out is that since the a/c isn't turning the fans on at all, could it also be telling the system not to turn the cars fans on when the car gets hot?

 

Does the air conditioning in your car work? If it doesn't blow cold air then the low pressure cutoff switch has disabled your A/C compressor clutch from engaging. If the compressor isn't engaging on the accessory belt then the fans won't switch on regardless of in cabin settings.

Are you sure the fans aren't running? They're pretty quiet relative to a 5.7 liter V8 but if your car gets that hot you should be able to hear them after turning the engine off in or near the red zone. When my car was on the verge of overheating I shut it down and the high speed fan continued to blow even after the key left the ignition (mine is also a 96).

Double check your fuses and relays. Most of the relays in the under-hood box are the same so try switching your fog light relay with the cooling fans to see if that changes anything.

It's odd that the fans powered on when you removed the temp sender pigtail because that means your PCM is responsive. How long have you had the car? Has it been tuned/programmed? Could it be possible that the PCM's fan settings have been altered from the factory tune out of operating range?

It is also a possibility that you have a faulty temp sender in the head that's giving you false readings on the gauge cluster. If that's the case your car may not be overheating at all.

 

I only bought the car 2 months ago, when I bought it the PW said the radiator was changed out by his mechanic because they said it was going bad. I brought the car to my local mechanic for an oil change a day after I bought it and while they were checking the whole car out the saw that the waterpump was leaking. So I had a guy I found on craigslist change the waterpump and while he did that he found there was no thermostat in the car. So obviously the PW or previous owners mechanic knew the cars fans didnt work and just took the thermostat out so the car never got hot.

No my air conditioning doesn't work, the PW said since the radiator was changed they took all the a/c out and never recharged it. but I did stick my finger in one of the A/C fill holes and there is pressure in it, but the fans do not turn on.

I'm sure the fans are not running, i've looked for them spinning and felt for air and never felt it.

I've switched the relays around and checked my fuses and tested the grounds.

I am not sure if the car has ever been tuned, but I talked to madtuner.com and I will probably be getting a new tuned and programmed PCM from them soon.

and there is no way my car is not overheating since the coolant goes over to the overflow tank and steams out the hole everytime the car gets about 3/4 there.

 

Any mods? You'd be better off buying a replacement PCM for your car from eBay then getting an expensive tune if it's stock. You did say that the fans powered on when you unplugged the temp sender which means that the PCM did in fact command the fans on, but the problem seems to be that the PCM is commanding them on at the factory temps of 226 and 235. It sounds like the previous owner used some sort of tuning software or a programmer to change the fan temps but moved the temps way out of operating range.

There can be a small amount of pressure in the A/C system but if you're not getting cold air then there isn't enough refrigerant in the system and the switch has disabled the compressor from running, therefore the fans will stay off.

 

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ye sounds like an a/c problem , however if i pull my water pump sensor still cant get fans to work. so going to check there at the a/c area for any probs. i hav more than once ran the car to nearly and hot on the temp guage. so i know there is a problem.

 

Either a. your fans aren't getting power (test the voltage on the pigtail when the car is warm) or b. your fans are dead (test them for functionality by using a 12v battery).