92 achevia cooling fan don't work

[papabear1983]

Hi, I have a 92 Acheiva and it has been running great, until a couple day's ago and it started running hot. Well we checked it and we found that it was leaking from the plastic radiator cap. Well we put a new cap on it and started it up and watched it, and it seemed to be ok and then it started leaking around the new cap. that is the only place it is leaking, so while I was watching it to see if it was leaking anywhere else I noticed that the electric fan wasn't working. I changed the fan motor and that didn't fix it so I was told by a friend that I could straight wire the fan and make it run all the time that the car was running. Well he told me how to do it and I did but the fan still don't work. Does anyone have a solution to fix my problem to get the fan to work so it will stop running hot? thanks a bunch .

[95OldsHO]

Im not sure how you tried to straight wire the fan but the ecm turns on the fan when it sees a ground signal, it doesnt use +12v to turn on the fan, +12v is always available to the fan but the ground is not, sounds wierd I know. It sounds to me like your coolant temperature sensor could be bad, Im not 100% sure on this but I believe the coolant temp. sensor reaches a certain temperature and opens/closes the circuit then provides the ground that the ecm needs to see to turn on the fan.

I know on the 94-95 models you can wire in a spdt switch(no center off)and control the fan manually as well as switch it back so that the ecm can control the fan normally, this is the best way to set this up because no matter what position the switch is in there isnt a risk of overheating- you must remember not to leave the fan running after turning off the car or a dead battery will be the result, if you wire the fan to run all the time or on your own switch you risk burning up the fan motor, or you could forget to turn it on when needed and overheat the engine.

Did you recently change the coolant out? sometimes on my car after I drain the coolant I get a pocket of air in the system, at this point I do get a small leak from the plastic radiator cap if the car is left to heat up even while driving if the coolant is low, once I go for a short drive the air is displaced and I can add more coolant mixture. My guess is that the pressurized air that built up in the system can leak by the cap and is carrying some coolant with it making it look like the cap is leaking. Last time I drained my coolant I took the car out for a short drive and it was running very hot, I made a right hand turn onto a street and the temp dropped to normal, I pulled over opened the hood and had what looked like leaking from the cap, I let it sit for about 10 minutes, then added more coolant mix and the temp has been at normal since then and no leaking at the cap.

[papabear1983]

Ok thanks I will get a sensor and try that and go ahead and change the coolant to and see what happens. I will let you know sometime this week. Thanks for the advise. This has been mind boggling .

[papabear1983]

Does anyone know where the temperture coolant sensor is located on the v6 3300 acheiva?

[papabear1983]

Ok thanks for the help , I played around with the fan motor and cleaned the green moisture that had built up in the plug, and it started working and keeping it cool at least for now. Thanks again for your help and input.