Primary cooling fan inop
07-29-2013, 04:58 PM
#1
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Primary cooling fan inop
My primary cooling fan will not operate. I have the secondary cooling fan rigged to a switch. I have a 180 degree thermostat installed. The cooling system builds pressure normaly. The radiator was new about 300 miles ago. My 1990 iroc will consistently continue to heat to 260 degrees and the primary fan never comes on. If I disconnect the coolant switch on the manifold the fan comes on. I figured it was a bad switch right? Nope. I replaced the switch twice with two different brands. It will not come on. Has to be an ECM problem now right? Any other ideas? I even changed the engine temp switch in case it was just an indication issue. I'm out of good ideas.
Last edited by IROCBOY; 07-30-2013 at 07:45 AM.
07-29-2013, 10:02 PM
#2
Re: Primary cooling fan inop
My primary cooling fan will not operate. I have the secondary cooling fan rigged to a switch. I have a 180 degree thermostat installed. The cooling system builds pressure normaly. The radiator was new about 300 miles ago. My 1990 iroc will consistently continue to heat to 260 degrees and the primary fan never comes on. If I disconnect the coolant switch on the manifold the fan comes on. I figured it was a bad switch right? Nope. I replaced the switch twice with two different brands. It will not come on. Has to be an EPROM problem now right? Any other ideas? I even changed the engine temp switch in case it was just an indication issue. I'm out of good ideas.
07-29-2013, 11:02 PM
#3
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Car: 1989 IROC & ROLL-Z
Engine: L98 Vortec FIRST TPI
Transmission: T56, Mech Speedo
Axle/Gears: G92 J65 3.27
Re: Primary cooling fan inop
Not sure what you mean by "primary fan"
https://www.thirdgen.org/forums/cool...ans-arent.html
https://www.thirdgen.org/overheating
Read these, carefully, so you have accurate troubleshooting material. Obviously the fan not coming on at all is a symptom. However, which side? When does it overheat? At what speed/conditions? How long has it been doing this? Are you sure your gauge is accurate? (IE you have checked it with a laser thermometer at the autoparts store) Need a little more history & info to help.
https://www.thirdgen.org/forums/cool...ans-arent.html
https://www.thirdgen.org/overheating
Read these, carefully, so you have accurate troubleshooting material. Obviously the fan not coming on at all is a symptom. However, which side? When does it overheat? At what speed/conditions? How long has it been doing this? Are you sure your gauge is accurate? (IE you have checked it with a laser thermometer at the autoparts store) Need a little more history & info to help.
07-30-2013, 07:36 AM
#5
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Re: Primary cooling fan inop
I have the secondary (passenger) fan rigged to a switch because the AC had been inop for a while and I didnt want it to effect cooling. So neither fan is controlled by the AC pressure switch anymore.
Last edited by IROCBOY; 07-30-2013 at 07:44 AM.
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