Cooling Fans will not turn on unless hardwired.

[Kats Euro]

I have a 90 lumina euro 3.1. The other day my temp gauge went sky rocket. One of my friends came over and checked it out. Neither one of my cooling fans will kick on when the temp raises to where they should be on. We checked the fuses and they all look good. Is there something else we can check. When we took the fuses out and took a wire and hard wired them. They ran. But when you would turn the car off it would stay running till you removed the wire. Is there some sensors that I could check or anything else. If some one knows where on the motor I could check it would really be appreciated. Thanks

[chevysrule]

hey i have a 1990 lumina euro 3.1 also and im having the excact same problem but only with one of my fans. geez

Originally Posted by Kats Euro

I have a 90 lumina euro 3.1. The other day my temp gauge went sky rocket. One of my friends came over and checked it out. Neither one of my cooling fans will kick on when the temp raises to where they should be on. We checked the fuses and they all look good. Is there something else we can check. When we took the fuses out and took a wire and hard wired them. They ran. But when you would turn the car off it would stay running till you removed the wire. Is there some sensors that I could check or anything else. If some one knows where on the motor I could check it would really be appreciated. Thanks

[Kats Euro]

If you figure out what is wrong with your chevy let me know. I really need to get this fixed. Especially in this hot weather. I can not be with out a car. For my hubby is using my 99. Thanks

[sysopt]

The engine coolant temp sensor may be bad. The fan relay might be bad. The wiring might be bad also. Youve ruled out the fan itself. That covers most of it.

[chevysrule]

i find it very annoying as it only happens once inawhile. i bought my car in novemeber and the thing never overheated until it started to get warm out. I need to fiqure out whats wrong with it as my man is too busy fixing his new car to worry about myn, but now im making him drive my lumina maybe then he will realize it overheats when it happens to hime and he can finally fix it! i was thinking maybe the thermostat was sticking but not to sure!

[Gary Magby]

Originally Posted by sysopt

The engine coolant temp sensor may be bad. The fan relay might be bad. The wiring might be bad also. Youve ruled out the fan itself. That covers most of it.

where is this sensor????

[jeffcoslacker]

Relay. Sensor. One or the other.

[jeffcoslacker]

If you disconnect the sensor, and ground the wire to the engine, the fan should start. If not, sensor might be the problem.

[jeffcoslacker]

Keep overheating that 3.1 and nobody's gonna be driving it soon....

[jeffcoslacker]

I think there is two sensors for coolant temp-one for the ECM and one for the gauge/light. The ECM one is suspect, since your gauge is working.

[richtazz]

the fan sensor is on the drivers side of the motor, just below and to the rear of the car from the t-stat housing. The relay is in the relay center under the hood just behind the passenger side headlamp. They are both cheap enough, so replace both and unless you have a broken wire, it should fix your problem. There are two relays, one for the A/C fan, the other for the main fan.