Cascade Crew

J-Dog-III · Posted: Mon Jan 22, 2007 8:16 pm Post subject: OverHeating / Rad Fan

Right now im kinda confused... i dont think that my radiator fan is coming on when the temp is going up. The other day on the way to school it was stop and go traffic up a pretty good grade hill, and i noticed the check Engine light came and and look at the temp guage as it jumped to 220. not 2 minutes later i pulled into the school popped the hood while it was running and no radiator fan was going.
After a week nothing happend until i was in the middle of town stopping at red lights when my car would idle then die suddley. Looked at temp guage and it spiked to 220 again. So i stopped at k-mart and let it sit for about 30mins and it was fine.

Any way to hook up power to the radiator to see if it's working or not? I could use sum diagnostice tips on this..

Al Hasse · Posted: Mon Jan 22, 2007 10:18 pm Post subject:

If you have a computer controlled fan (like my 3.1 V6 does), the fan comes on at around 230 degrees or anytime the AC compressor kicks on (if equipped). As an added sense of security, some will add a manual switch to the cooling fan as well as keep the computer control to it. As for your check engine light, you need to be able to pull the code from the computer.

Here's a how to for reading the codes - all you need is a paper clip to short pins A and B together, the connector is located under the driver's side dash.

http://www.obd-codes.com/faq/read-gm-2-digit-obd-codes-free.php

and a list of codes

http://www.thirdgen.org/service-engine-light-error-codes

My best guess is that your coolant temp sender is going bad, it sits next to your thermostat on the intake manifold.

J-Dog-III · Posted: Mon Jan 22, 2007 11:22 pm Post subject:

So my coolant temp sensor could be bad making the car stall out and die? (Auto tranny)

Al Hasse · Posted: Tue Jan 23, 2007 1:10 pm Post subject:

I'm not saying that that IS your problem, but yes it can cause the car to die (happened to me a few years ago), but it is a place to start.

The way I understand this is when the ECM receives the wrong temp, it commands the fuel mixure (rich for cold and lean for hot) incorrectly, which also messes up the emissions control, and the temp at which the cooling fan comes on will be incorrect. Before you spend any money on parts you don't need, you should try to pull the codes out of the ECM and get a place to begin looking.