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CelticSkyhawk
06-01-2004, 10:01 PM
I replaced my thermostat over the weekend for an overheating problem. I replaced with the Hypertech from PFYC. After a minor setback with the hoses that cross through the throttle body, I've got everything cleared up.

Because I was paying attention and had my a/c shut off, I've noticed that my fans won't come on. My temp is going up to about 215 before it begins to hold position and this only happens in stop and go traffic, not normal highway driving. The fans don't come on automatically, but if I turn on the a/c or heat the fans do come on, so it doesn't appear to be a relay or fuse.

Reading the sticky, it looks like the fan switch could still be bad, but how is that possible? Is there more than one switch? I was thinking my coolant temp sensor could be going until I read this, now I'm not sure. Any help is appreciated.

schizm99
06-01-2004, 11:24 PM
Sensor or relay..

CelticSkyhawk
06-02-2004, 09:38 AM
Do the relays just pull straight out of the fuse block? According to Haynes, there are two of them, if I remember correct.

2Dambad
06-02-2004, 10:07 AM
Your problem sounds normal. When the car is setting if traffic, there is not as much air getting to the radiator. Without the AC on, the fans wont turn on until around 215 I believe. You can either turn on the AC earlier to get the fans on, get a fan switch to turn the fans on manually, or get a new computer with lower temp settings.

CelticSkyhawk
06-04-2004, 09:53 PM
Your problem sounds normal. When the car is setting if traffic, there is not as much air getting to the radiator. Without the AC on, the fans wont turn on until around 215 I believe. You can either turn on the AC earlier to get the fans on, get a fan switch to turn the fans on manually, or get a new computer with lower temp settings.

Thanks for the information. Now if that's the case, and the fans won't come on until 215 or so, what's the purpose of getting a 180 Hypertech Thermostat? With the a/c on, my temps stay around 200, which I've heard is not uncommon for the Hypertech during summer months. Is this accurate?

Mike Jung
06-05-2004, 09:20 PM
^

The 180 thermostat opens earlier, which results in the engine coolant going the the rad sooner.

But if the engine coolant heats-up; then there is not much you can do about it until the fans kick-in or you get some decent cool air flow by driving.

Having the high-speed manual fan speed in this situation with that 180F thermostat would be the best combo.

In cooler weather your car's engine coolant will run cooler than say with a stock 195F version thermostat.

Since you changed the thermostat; did you also change the Dex-cool ?
It seem to help me after getting my Dex-cool drained/flushed & re-filled.

Having a real 'synthetic' (that contains PAO's) motor oil also seems to help keep the engine coolant temps down alittle.
I use Mobil 1 & it helps keep the engine coolant down alitte bit.
I'm typically running (85C/185F) 1-line below half (90C/194F) with a stock 195F thermostat; unless I'm stuck in traffic (or hard on the throttle).

CelticSkyhawk
06-07-2004, 09:57 AM
Talked it over with a mechanic associate of mine. He believes the auxillary fan switch may be disconnected, corroded, or bad. He told me it should be up on the fan but I'm not real familiar with what it would look like. I couldn't find anything in the Haynes manual. Does anyone know where the fan switches are?