Hi guys, you helped me when I was going to change my engine & now I'm back with another question.

I have a '85 Firebird with a 2.8 out of a '87 (dunno if that matters)

Took it out for the first drive since I changed the engine & overheated after around an hour! Turned out that the fan wasn't turning on. First we did the easy thing & changed the fuse, but that didn't work. Then the check engine light came on, with a code of 23 - Manifold Air Temp Sensor. Seemed like that would be the problem, so we switched to the one off the original engine, since that one had been working up to the point the engine died. Didn't work! Still getting the code 23. No wires seem to be broken or unattached. The fan doesn't turn on when the A/C's on either (saw in another post to check that?). My dad used a wire to get around the sensor - forgive me, I'm more of a driver than a mechanic, so I'm not sure exactly what he did - but that didn't get the fan on either.

Now, the thing is, I'd assume it was the fan itself, were it not for the sensor code coming up. Could it be that the fan not working is throwing off the sensor? Could there be something wrong between the sensor & the computer? Is there something else that could affect this??? I don't have lots of money to go get this fixed by a mechanic, so if it's something we can find & do at home, that'd be great! PLEASE HELP!!!

 

I would test for power at the fans, and try to jump power to them to see if they actually turn on, if that works... and they do turn on with straight power, then move on the the Fan relays and check for power there, and basically work you way back to the ECM & sensors as they will cost the most I would think.

 

I replaced my fan, they cost about $55...

takes about 15 mins...