fan not coming on
 

hey i've got an 88 GTA with a single fan. I've been doin a bit of work on this car. I replaced the fan switch on the intake when i put on the miniram. The fan was working and coming on at about 195-200 deg and shutting off when it cooled back down. Last night after i changed the starter i noticed the temp was rising fast and the fan would not come on. I wired it directly to ground so it would run all the time. I took it for a short ride and the temp shot up to about 240 and suddenly shot back down to about 210. My question is would a stuck thermostat cause an incorrect reading at the fan switch. Causing the computer to not kick on the fan.

Re: fan not coming on
 

Could it be the fan switch on the side of the block? It might have gone out. I had this problem and it caused my car not to cool at all.

If your car was an original gta I would think it would have the dual fan setup but Idk.

Re: fan not coming on
 

this is a single fan model so the sensor for the fan is on the intake manifold next to the cold start sensor. There is another one on the drivers side that one just runs the gauge though. I'll change out the thermostat and re-wire the fan back to stock and try it again.

Re: fan not coming on
 

Check for a blown fuse, mine kept buring them out, then after i fixed that I burned up my motor, in the fan. Check the fan, motor too, I cant remember but I think I just ran 12v to it and noticed it didnt turn, but there is an inline fuse at least in teh camaro on the pass, fender wall, by the battery

Re: fan not coming on
 

If your temp is spiking high and then immediately coming down from 240+ and your fan is always on, its usually your thermostat not opening correctly. Once your thermostat finally opens colder coolant from your radiator gets to your engine block and you see the temp drop to normal.

Re: fan not coming on
 

My original question was do you think the stuck thermostat could be the cause of the fan not coming on. I know its not a fuse, the relay, or the fan motor because when i grounded the green/white wire from the computer to the relay the fan comes on. I'm not sure if the car came with dual fans or not. When i bought it, it didnt have a motor transmission or wiring harness. I swapped one in from am 86 TA with a 305 tpi

Re: fan not coming on
 

No the thermosat not opening would be a reason for it not turning off... check the sensor again.

Re: fan not coming on
 

Your thermostat and fan are not interconnected in that way. The thermostat opens and closes without any electrical/relay connections and is simply a small valve that opens up when hot. If your thermostat was stuck closed you'd see temps rising to well above 220 even after your fan kicked on. If your thermostat was stuck open then your engine would simply take a long time to warm up from a cold start and the fan would click on and off more frequently than is normal. Either way when your engine got too warm your fan would still turn on. It sounds like your Coolant temperature sensor is at fault if, even after the car reaches 220+ your fan isn't kicking in.

The CTS is a cheap to replace $10 part from autozone/pepboys just watch for coolant when you pull the old one out

Re: fan not coming on
 

I am actually thinking that since my coolant level was low and the thermostat was stuck, the sensor never had any coolant going across it to get any reading. I'm going to buy another one just to be on the safe side. But im going to try it out anyway. Ill post on here if it works after the thermostat swap, or if it was the coolant temp sensor. Thanks for the suggestions guys.

Re: fan not coming on
 

hey guys, i changed out my thermostat, added some coolant, and wired the fan relay back to the computer. The fan came on right at 175 like the chip was programed. I had to add about a half a gallon of coolant though, must have not had enough coolant to heat up the sensor. Thanks for all of the info guys.