I will try to keep this as short as possible. Car has had many heating issues for the past year or so. A friend is driving the car currently so I don't know personally what is happening when you presently drive the car.

The thermostat has been replaced, all the hoses are replaced, the radiator has been replaced 3 times due to the radiators bursting. This was happening due to the fan not coming on, as far as I can tell. The fans have been repaired. Whats happening now is the car overheats even when driving. Turning on the AC helped slightly I was told, but The condenser is not even attached to the main pulley. The support pulley for the ac system broke and now the belt can not attach as supposed to. So now hitting the ac switch effectively does nothing.

I don't think the coolant is leaking, but I honestly don't know for certain. The water pump and timing belt were replaced about 6 months ago. The car has maybe been driven 5k miles since then. Right now I am really just looking for ideas. The engine coolant temp sensor has been replaced.

I do have a question concerning that, though. What is the sensor that sits along where the thermostat goes in? I thought that was the ECT sensor goes but when I had the mechanic replace it, that part was unchanged. And they handed me the old part. It was definitely replaced. But, that sensor by the thermostat looks the same. What does it do and could that be a factor? I think literally everything in the cooling system is less than a year old other than that mystery sensor.

 

You have three(3) ECT "sensors"
The ECT sensor, supplies ECU/ECM with engine temp, 2 wire sensor under distributor.
The ECT switch, controls rad fan, 2 wire sensor on thermostat housing.
The ECT sending unit, supplies engine temp. to the temp. gauge in cluster, 1 wire sensor next the ECT sensor under distributor.

There is no belt connected to the A/C condensor, you must mean A/C compressor.

Turning on the A/C should turn on the A/C condensor fan, even if the compressor is not running.

I would confirm that the rad fan is turning on, and I would check the thermostat, even if it is new, it can still be bad. 94

 

Yes I meant compressor lol.. thanks. How long does it take for the AC fan to come on? We tried that and no fan was spinning. We didn't wait long, though. I don't think its the thermostat. We tested the old thermostat to make sure and it turned out to be functioning properly. And the problem hasn't changed... so I am assuming the new Thermostat is also working. We didn't swap them back. The old one is a cheap autozone one and the new one is a nicer looking cheap napa one. ;-)

I don't recall the wire count on the sensor I am thinking of, but its near under the distributor. Its right after the long bottom hose from the radiator just before the thermostat.

I have been doing a lot of forum reading and a lot of people are talking about pressure testing, milky oil, bad pistons. A mechanic did a pressure test on the valves... I think thats what I am thinking of... and they tested good. Not even considering the age of the motor the numbers were good. And the oil is fine.

My friend said he didn't notice any leaking of coolant at all. What is your opinion on it being a now faulty radiator cap? They seem very flimsy. Or clogged radiator?

It got so bad at one point the mechanic who did a lot of the work on the hoses/gaskets/radiator said he thinks the cooling system is possessed on this car. :-p

Thanks for your information so far. I'll do long check of the radiator fan and see if it kicks on. How likely is it that the gauge alone is faulty? The engine may not even be overheating?

 

A bad gauge is a possibility, the ECT sending unit, is the one wire sensor under the distributor, it is what supplies info to the temp. gauge.

Do you still have the old sensor they replaced, if so, how many leads/terminals does it have?

Try this, unplug the ECT switch on thermostat housing with a green lead and a black lead, with the ign.switch on, use a paperclip to jump the switch plug, connecting the black lead to the green lead, rad fan should turn on. 94