So I've followed advice on adding the hayden aftermarket adjustable fan switch on my 89 305tpi automatic, and even put in a 170 degree thermostat. The Hayden switch is a piece of crap as the adjustment **** breaks easily, and you can't really adjust it afterwards. My fans now come on at about 170 degrees and don't let the car get any hotter than this. Should I be happy or is this going to cause problems by not reaching oem operating temperature?

After installing this fix, i've had a burnt distributor cap/rotor, broken mass air flow sensor, and broken throttle position idle air control sensor all WITHIN two weeks.

PLEASE HELP!!!

 

Is your car hitting closed loop operation? Aside from a possible effect on that, the only other problem you will have is lack of heat in the winter. The lower you go with the stat, the less heat you'll have in the winter...for the most part.

 

IIRC closed loop in the computer is set around 104F.

 

Ok, well, that answers that question..lol. I rekon I was just a little off.