First off, correct me if I am wrong, but in a TPI car, one fan is supposed to run ALL THE TIME, and the secondary is supposed to be on between 185 and 220?

Well, neither of my fans come on.... EVER anymore. I have a 160 stat, and the if I city driving, the temp rises uncontrollably, but when I am on the highway it comes right back down.

What can I do to get BOTH of my fans running, and running correctly? ANY help will be greatly appreciated.

------------------
1989 Chevrolet Camaro IROC-Z
L98 - 350c.i. TPI, rebuilt 700R4 auto w/shift kit, Dual catalyst Monza PaceSetter Cat-Back, SLP 1 5/8 Coated Headers, 3.23 Posi rear, Hypertech Thermomaster chip with 160stat, MSD 6A, March Under-Drive pulleys, AFPR, K&N's, !Air Box w/ Ram Air, moddified MAF, !TB Coolant, Spohn Dual Cat SubFrame Connectors, Alarm, Keyless entry, remote starter, 92 Z28 AeroWing, Brand New Paint (6/21/01)

Future: ZZ4 TPI w/EGR, T56, 3.42 or 3.73, Spohn strut tower brace and LCA's, Accell Universal 24# injectors

More info and pics on my webpage:http://go.to/iroc-z

AOL IMer: GPA 0point0

 

My 87 TA TPI fans do not run all the time. One fan will come on at about 220 and the other a little higher. The one fan will run if the A/C is on and gets its signal from the A/C switch relay. I put a direct ground to my right fan and ran a switch to the dash so I can manually control the fan in case of overheating. Just run a ground wire from the fan sensor to your switch and from the switch ground it to the frame and when you turn on the switch your fan will come on.

------------------
87 TA, 305 TPI, Custom CAI, ACCEL 8mm wires,ACCEL Super-coil, ACCEL Plugs, JET TPI Airfoil, Cherry Bomb Muffler
"35 yr old helo pilot
with a cool new toy my 17 yr old son wants"
The Phoenix Project..click to see my project car
Trans Am stuff and GIRLS, GIRLS, GIRLS!!!!!

 

Also, the reason your fan is not working in the first place is probably a bad relay.

------------------
87 TA, 305 TPI, Custom CAI, ACCEL 8mm wires,ACCEL Super-coil, ACCEL Plugs, JET TPI Airfoil, Cherry Bomb Muffler
"35 yr old helo pilot
with a cool new toy my 17 yr old son wants"
The Phoenix Project..click to see my project car
Trans Am stuff and GIRLS, GIRLS, GIRLS!!!!!

 

The driver's side fan is controlled by the ECM at approx 222 degrees; the passenger side fan is controlled by the a/c and the auxilliary coolant temperature switch, approx 238 degrees. The ECM reads that line and should turn the primary fan on if the secondary fan is on.

If neither fan works, you need to investigate two things.

1) Do you have power to the fan relays ? There's a big orange wire that goes to both fan relays. If it's hot (it should be hot all of the time) then you're good to go to #2. If it's not hot, then you probably have a burnt fusible link. It's right off of the battery positive cable on my '89 Pontiac; I believe the Chevy is similar. I had to backprobe the wire with a pinpoint tester to find a break in my wire.

2) If you have full-time hot to the fan relays, you need to ground the control pin and see if the fans come on. This will test your relays. If they come on then there's a problem in your control wiring. If not, then I'd suspect either the relays or the fans.

 

OK... thanks. Now, I know F-Bodies pretty well from browsing the boards here and driving mine for the last 3 years.

2 things that are still a mystery to me... automatic trannies and cooling systems. The point is, where are the fan relay(s), how do I change it/check it? Where can I get a new one from?

 

My Pontiac has the relays on the passenger side radiator core support between the radiator and fender. There's a couple of relays attached to the bracing there.

Any automotive parts house should carry those relays. I've bought them at both small and large chain stores.

 

I am also experiencing the same thing. Both fans do turn on, but not all the time. If i am driving on the highway, i have no overheating problems, but at the lights or stop n go traffic; the temp just rises to over 240 even with the A/C on! At other times the temp gets near 240 and then starts to cool down with the A/C on. Thats when i know my fans are working and so are my relays.
I don't know why sometimes they work and at other times they don't. The relays were checked out and they are fine. What could it be?

P.S.
When i see the temp get near 240, i watch it very carefully to see if it starts to drop, and if it doesnt i pull over to the side, pop the hood and shut it off. Is this ok?