Engine fan running some times
 

Hope to get some help with this one guy's.I have a 2002 sl -1 which I bought used. I noticed that the heat wasen't very warm in car so I replaced the T-Stat, although I did get a little more heat the temp guage went almost to half.I checked the t-stat from a bunch of different places and it calles for a 188 degree one to be installed.On top of that I also can only intermittenly get the motor fan to come on for a short period of time then it goes off, I tried using the A/C mode and I still coulden't get it to come on .I checked the reley's visually and there was some corrosion on all the terminals,so I just brused off the best I could and still no go. Please help.If the refrigerent is low will this keep fan from coming on ? When I first start the car and put it on defrost the fan will come on but after a short drive the fan goes off again.

OK -- are you talking about the fan underneath the dashboard inside the car, or are you referring to the fan next to the radiator ??

Yes I am referring to the radiator fan.I also want to add that when I have seen it run both in A/C mode and with the Defroster mode position both the compressor and radiator fan run together,but after a few miles they both shut down and I can not get them to come on again,thats why I am questioning weather low refrigerant would cause this .Thanks

Le title states engine fan Ocean lol
Im not sure about the refrigerant, however, I will default to a viable culpret - the Engine coolant temp sensor can be going bad - might explain funky gauge reading. I recently replaced my thermostat and my gauge reads alittle over the first hash mark during normal driving. ( well, I actually replaced half my cooling system, so that might make a difference aswell.)
However, before doing something with that try switching the relay with another, its possible it could have gone bad.

There are a few threads on here about the cooling fans, maybe some searching might help even more

It's winter, and cool air will cause this. The cooling fan should not come on till the heat gauge hits apoox the 3/4 mark on the temp guage.

However, I remember on my car when the a/c was on (no matter what season) the cooling fan was always on...

A/C
low refrig level will cause both the compressor to kick off as the low refrig switch will inhibit the compressor from kicking in. The cooling fan will also not come on under these circumstances. Borrow a gauge set from autozone or similar and report high and low side pressures here.

General cooling fan operation:

The ECTS resistance is interpreted by the PCM to determine coolant temp. With a properly functioning ECTS, per sw2cam, the fan doesn't kick in until above the 3/4 tick on the dash gauge. People get scared by this but it is seemingly by design, and once the fan kicks in, the temp gauge (and coolant temp) drop. This behavior is of course independent of the A/C charge status. So don't expect the fan to come on until the gauge gets up there.

As for relay -- if there's corrosion on the contacts, there is likely corrosion in the socket. I'd swap it per Rube and let the car idle in your driveway until the temp rises, the fan kicks on (above the 3/4 tick), and the car cools back down. By doing so, you'll have verified proper operation of your cooling system.

Changing out the ECTS and connector with GM sourced parts is also recommended since these almost always failed and send bogusly low temp readings to the PCM.

derf I'm glad you typed all that. I was just not in the mood to look the subject up then copy and paste it for the 5,000th time nor was I in the mood to type out the entire explanation of this subject again. People are to lazy to read the forums. I'm to lazy to answer the same question more then 10 times.

I totally understand,I did a search but was unable to find what seamed to be able to help me out.I've been on many forums in the past and present and when I'm able I like to try and help out.That's what I have found most if not all talk Forums are all about.

Fan and compressor issues
 

O.K. I have more information,I can not get the compressor to kick on when I put the front defroster in the on position,in the past I would always hear and see the compressor clutch engage when in defrost ,Not now it won't engage at all unless I take the high pressure switch terminals off and jump them , then both the compressor and fan will kick on, I also installed a new compressor relay and it made no difference.I have to order a new pressure switch since no one has one in stock. If anyone has any positive info please enlighten me. Thanks