i recently acquired an '87 iroc with thermo-master chip and 160* thermostat. it has dual electric fans and i was wondering if the passenger fan should always be on and the driver's side kicks on at 160* or is it opposite because the passenger fan never comes on and the engine seems to run hotter than it should be with all of these "low temperature" accesories. please forgive me if this has already been answered, but i am relatively new to electric fans. could it be a fuse or a switch or is the passenger fan motor itself???

 

'87, a good year! And an anniversary year for the Camaro.

The driver side fan(primary) is controlled by the computer/chip programming. So it sounds like its working fine. But the passenger side fan(secondary) runs independently of the computer and is controlled by a fan switch(like a sensor) in the passenger side head between spark plugs 6 & 8.

And since the secondary fan isn't coming on, it could be the switch, it could be its fan relay, it could be its motor, it could be fuse-related(though I doubt it is), or it could be something else, very simple... the factory fan switch might never have been changed to a lower temp switch.

The factory switch kicks the secondary fan on around 240*. And it's likely your engine isn't getting anywhere close to that temp to make the fan come on. To test to make sure everything's working, splice into the wire to that fan switch and touch it to the chassis(grounding it). If the fan kicks on, then everything's fine, and that's the problem--a high temp switch. If it doesn't come on, then it could be one of the other problems mentioned.

So if it works, then you could either run that spliced wire to a toggle switch inside the car so you can control it when you want to, or you could change the switch to a lower temp switch so the relay will control it on its own. Either way, you've already noticed that to keep temps that low in traffic, your primary fan needs assistance from the secondary fan.

 

thanks for the response