Fan Problem
#1
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Car: 1989 Pontiac Formula 350
Engine: 350 tpi
Transmission: 700
Axle/Gears: 3.27
Fan Problem
OK, here is my problem. 1989 Formula 350 with the dual fans.
If the A/C is not on neither fan comes on no matter how hot it gets. If A/C is on both fans kick in around 220 and cool it down.
What do I go after first to try and get the fans to kick on without the A/C running? Not fun running the A/C when it is 35 outside.
Thanks
If the A/C is not on neither fan comes on no matter how hot it gets. If A/C is on both fans kick in around 220 and cool it down.
What do I go after first to try and get the fans to kick on without the A/C running? Not fun running the A/C when it is 35 outside.
Thanks
#2
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Car: 80 SE/TTA;88 T/A GTA;86 T/A
Engine: 4.9L Turbo; LT1; empty
Transmission: TH350; T56; empty
Axle/Gears: 3:23 disk; 4:10 disk ; 3.42 disk
Re: Fan Problem
i've been told that the passenger side head has the temp switch for the fans to activate.
#3
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Car: 1989 Pontiac Formula 350
Engine: 350 tpi
Transmission: 700
Axle/Gears: 3.27
Re: Fan Problem
I am pretty sure the temp switch on my tpi is under the air intake on the plenum. AllData shows it there but of course they also show the relays up by the headlights when they are on the firewall in front of the driver so who knows.
#4
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Car: 80 SE/TTA;88 T/A GTA;86 T/A
Engine: 4.9L Turbo; LT1; empty
Transmission: TH350; T56; empty
Axle/Gears: 3:23 disk; 4:10 disk ; 3.42 disk
Re: Fan Problem
the temperature sending unit is under the TPI i believe, but the fan switch itself is on the passenger head, but i'm going by TBI...but i do know there are two different sensors. Thats why your guage should still work and your fans don't, i have the same exact problem, but yet to get to it.
#5
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Car: 1989 Pontiac Formula 350
Engine: 350 tpi
Transmission: 700
Axle/Gears: 3.27
Re: Fan Problem
I have now replaced both relays and still the same problem. I bought a fan temp control and it only has one wire. Exactly how in the heck do I find the one in the head because the one in the front of the tpi assmbly has two wires. Thanks
#6
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Car: 91 rs,1 92 rs,92 b4c/1le
Engine: 5.0tbi,5.7 tune port/5.0tpi
Transmission: 5spdx2 and t56
Axle/Gears: 3.08,3.73,3.42
Re: Fan Problem
between second and third plug on paseenger side cyl head the connector is most likely melted
#7
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Car: 87 Camaro Z-28
Engine: 305 LG4 w/ E4ME carb
Transmission: 700R4
Axle/Gears: 2.73
Re: Fan Problem
hum. for a carb model the fan control switch is just above the starter between 6&8 spasrk plugs; a spark plug socket fits it and doesn't damage the end of the fan control sensor. IIRC from diagrams it was the same for others but maybe not... let us know where it is on yours
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#8
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Car: 1989 Pontiac Formula 350
Engine: 350 tpi
Transmission: 700
Axle/Gears: 3.27
Re: Fan Problem
Is this one of those things easier gotten to from below or thrugh a wheel well when the vehicle is jacked up? I can barely even see the spark plug wires let alone any other wire from above.
#9
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Car: 87 Camaro Z-28
Engine: 305 LG4 w/ E4ME carb
Transmission: 700R4
Axle/Gears: 2.73
Re: Fan Problem
from under the car; shine a flashlight up over the starter and look for the fan control switch in between 2 spark plugs; found it's best to drain the coolant first
#10
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Re: Fan Problem
This from a carbed car (the switch won't "look" like yours):
https://www.thirdgen.org/forums/atta...cs-thermal.jpg
JamesC
https://www.thirdgen.org/forums/atta...cs-thermal.jpg
JamesC
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