I've got a 94 z-28 and I'm having a problem with the fans not turning on unless the AC is on. I did a search and did a procedure that Shoebox told some gut to do, it involved grounding two wires by th Passenger side strut tower, It basically tells me that both my fuses and relays are good. I also replaced the sensor on the waterpump twice, and still no go. Reset the Ecm and that did'nt help either. Do any of you guys have a suggestion? Thanks

Paul

 

Got any way to scan and see what the PCM is seeing for engine temp? Plus you can see if the PCM is commanding the fans on when it gets to the fan ON temp.

 

No i have no way of scanning it, I checked out your tech site and found out that i am getting 5 volts at the sensor plug, any thing else i should try?Thanks again

 

My bet is its your ECT. Mine went out and it never even went into closed loop or turn the fans on. Does your car run rich all the time? That is a sign that it isnt going into closed loop.

Id suggest buying a new ECT (like $6 from autozone). If the old one isnt bad, bring it back.

You need a multimeter to test the ECT. You can test the old one against the new one with boiling water.

-Stu

 

I have a fan switch on my car...my fans wouldn't turn on unless the AC was on, fan switch works good......especially in the staging lanes at the track

 

Disco, what exactly is the ECT? and when i check it do i just check the continuity and make sure that it's reads 0 ohms or what. Also my SES light just came on this morning but then shut back off, hopefully it's all related. Thanks again.

Paul

 

He means the sensor. Info on ohms readings and stuff is on my site that you already looked at.

 

If you replaced the sensor in the Water pump that is your ECT. If you could scan you would see if it was reading properly, maybe the ground there is bad? Maybe the wiring to it is open?

 

ECT stands for engine coolant temp sensor. It is under the water pump. A bad ECT will usually set off the SES light. This will usually give you a code with something to do with closed loop and such. Sorry i forgot the trouble code #.

Good Luck,
Stu

 

Yeah already replaced that sensor, i guess the only thing left to do is find someone with a scan tool. Thanks again

Paul Simmons

 

is it code p0125? My car just threw this code today.

 

It wouldn't be that code for a 1994, but you might want to check your sensor.

 

Haven't found a scan tool yet but the SES light comes on like maybe once every two weeks and shut off with a few minutes? I lost.