coolant temperature switch....replacement values???
Thread Starter
Drifting
Joined: Oct 2003
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From: CALGARY ab
coolant temperature switch....replacement values???
there are two temp sensor 89 L98
1) located between 7&8 which is spade type
what is it's function? gm part #?
2) located between 1 & 5 which pin type
what is it's function? gm Part #?
want to replace one of the sensor to tell ECM, for fans to come sooner EX on @ 210*F off @ 195*F.. what is the gm part# for this sensor.
ecklers has one... BUT there should be a part that is available from auto parts store..just need the numbers..does any one know that could help me with this part?
1) located between 7&8 which is spade type
what is it's function? gm part #?
2) located between 1 & 5 which pin type
what is it's function? gm Part #?
want to replace one of the sensor to tell ECM, for fans to come sooner EX on @ 210*F off @ 195*F.. what is the gm part# for this sensor.
ecklers has one... BUT there should be a part that is available from auto parts store..just need the numbers..does any one know that could help me with this part?
Burning Brakes
Joined: Jan 2002
Posts: 993
Likes: 4
From: Glen Burnie MD
If your 89 is like my 86, then the sensor between 6 & 8 is for the display on the dash, the one between 1 & 3 is for the aux fan in front of the radiator, and the ones in the manifold underneath the throttle body tell the ECU what the temps are.
On mine, I was able to have my chip reburned to change when the fans come on. I tried a lower-temp sensor, but it didn't work for me (wrong year - it was designed for 84/85).
[RICHR]
On mine, I was able to have my chip reburned to change when the fans come on. I tried a lower-temp sensor, but it didn't work for me (wrong year - it was designed for 84/85).
[RICHR]
Race Director
Joined: Sep 2000
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From: The Top of Utah
Originally Posted by korvette4u
there are two temp sensor 89 L98
1) located between 7&8 which is spade type
what is it's function? gm part #?
2) located between 1 & 5 which pin type
what is it's function? gm Part #?
1) located between 7&8 which is spade type
what is it's function? gm part #?
2) located between 1 & 5 which pin type
what is it's function? gm Part #?
2.) The axillary fan switch, located between the plugs for cyls, 1 & 3, on the left side of the engine, is 14043276.
3.) The engine coolant temp sensor for the ECM is in the front of the intake manifold, facing forward. Part number 25036979.
The ECM uses that sensor for ALL engine functions. The prom has to be reprogrammed to change the temperature of the main fan actuation.
RACE ON!!!
Thread Starter
Drifting
Joined: Oct 2003
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From: CALGARY ab
Originally Posted by CFI-EFI
1.) The dash gauge sensor, located between the plugs for cyls. 6 & 8, on the right side of the engine, is 25036135.
2.) The axillary fan switch, located between the plugs for cyls, 1 & 3, on the left side of the engine, is 14043276.
3.) The engine coolant temp sensor for the ECM is in the front of the intake manifold, facing forward. Part number 25036979.
The ECM uses that sensor for ALL engine functions. The prom has to be reprogrammed to change the temperature of the main fan actuation.
RACE ON!!!
2.) The axillary fan switch, located between the plugs for cyls, 1 & 3, on the left side of the engine, is 14043276.
3.) The engine coolant temp sensor for the ECM is in the front of the intake manifold, facing forward. Part number 25036979.
The ECM uses that sensor for ALL engine functions. The prom has to be reprogrammed to change the temperature of the main fan actuation.
RACE ON!!!
BTW: thanks for the part numbers CFI-EFI
Race Director
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From: The Top of Utah
Originally Posted by korvette4u
so you can not replace #1 or # 2 with different lower on /off switch? kinda like tricked the ecm into thinking that it should turn fans on @ 235*F
BTW: thanks for the part numbers CFI-EFI
BTW: thanks for the part numbers CFI-EFI
You can change #2 to alter the "ON" point of the axillary fan.
Number 3 tells "The ECM the engine for ALL engine functions". If you change the value of #3, you will change what the ECM sees for all it's functions. The engine would run terribly.
If changing or reprogramming the prom for the on-off temps you want, is not something you want to do, you can tie the main fan to the aux fan, with a cooler switch. Or you can simply add a manual switch for the main fan.
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Racer
Joined: Nov 2004
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From: Iowa Go Hawks
Okay here is what I did with my fans on my 89
I installed a 195 degree on and 180 degree off fan switch where the aux fan switch is on the drivers side cylinder head between cyl 1&3. I connected it to the green-white wire on the aux fan relay then I ran another wire to the main fan relay and connected it to the green white wire on it. Now both fans come on at 195 and turn off at 180. The main fan still runs when the air conditioning is on by being controlled by the ECM. I feel a lot more comfortable by being able to control the fans at lower temps and having the engine run cooler in town. Just my 2 cents worth.
I installed a 195 degree on and 180 degree off fan switch where the aux fan switch is on the drivers side cylinder head between cyl 1&3. I connected it to the green-white wire on the aux fan relay then I ran another wire to the main fan relay and connected it to the green white wire on it. Now both fans come on at 195 and turn off at 180. The main fan still runs when the air conditioning is on by being controlled by the ECM. I feel a lot more comfortable by being able to control the fans at lower temps and having the engine run cooler in town. Just my 2 cents worth.
Burning Brakes
Joined: Jan 2002
Posts: 993
Likes: 4
From: Glen Burnie MD
Originally Posted by CFI-EFI
Or you can simply add a manual switch for the main fan.
[RICHR]
Thread Starter
Drifting
Joined: Oct 2003
Posts: 1,594
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From: CALGARY ab
Originally Posted by mesteffen
Okay here is what I did with my fans on my 89
I installed a 195 degree on and 180 degree off fan switch where the aux fan switch is on the drivers side cylinder head between cyl 1&3. I connected it to the green-white wire on the aux fan relay then I ran another wire to the main fan relay and connected it to the green white wire on it. Now both fans come on at 195 and turn off at 180. The main fan still runs when the air conditioning is on by being controlled by the ECM. I feel a lot more comfortable by being able to control the fans at lower temps and having the engine run cooler in town. Just my 2 cents worth.
I installed a 195 degree on and 180 degree off fan switch where the aux fan switch is on the drivers side cylinder head between cyl 1&3. I connected it to the green-white wire on the aux fan relay then I ran another wire to the main fan relay and connected it to the green white wire on it. Now both fans come on at 195 and turn off at 180. The main fan still runs when the air conditioning is on by being controlled by the ECM. I feel a lot more comfortable by being able to control the fans at lower temps and having the engine run cooler in town. Just my 2 cents worth.
thanks
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Race Director
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From: The Top of Utah
Originally Posted by rrubel
I did this for my aux fan, using a relay from the junkyard and wiring a switch under the dash by the ALDL connector. Just be careful where you route the wires and mount the relay; the driver's headlight well looks like PLENTY of usable space, but believe me - the light needs it ALL. Had all my wiring nicely in place, turned on the lights, and ripped it all out... RGH!
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Thread Starter
Drifting
Joined: Oct 2003
Posts: 1,594
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From: CALGARY ab
Originally Posted by CFI-EFI
There was no need for an additional relay. Just hook the switch up to provide an additional ground path for the primary circuit of the stock relay. Also, if you lose track of the temps, the ECM and A/C will STILL kick the fan in when called for. It is as simple as a switch and two lengths of wire. You did WAAAAAY too much work.
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just add the switch...did this.. maybe the trick is to have the secondary fan come on early by changing that 1-3 temp switch and still use manual switch if thing get hot...... 
Racer
Joined: Nov 2004
Posts: 363
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From: Iowa Go Hawks
Originally Posted by korvette4u
this is what i want to do....i did manual switch.. PITA...what was the part # of the 195* F switch?
thanks
thanks
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
Try MAM, Eckler's or Summit for the lower temp aux fan switch.
I put a wiring method in C4 Tech Tips on hooking up the aux fan switch to drive both fan relays. You can get the clip on connectors from Radio Shack so that no soldering is necessary and you can hide everything inside the large wiring harness.
I put a wiring method in C4 Tech Tips on hooking up the aux fan switch to drive both fan relays. You can get the clip on connectors from Radio Shack so that no soldering is necessary and you can hide everything inside the large wiring harness.
Thread Starter
Drifting
Joined: Oct 2003
Posts: 1,594
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From: CALGARY ab
Originally Posted by 65Z01
Try MAM, Eckler's or Summit for the lower temp aux fan switch.
I put a wiring method in C4 Tech Tips on hooking up the aux fan switch to drive both fan relays. You can get the clip on connectors from Radio Shack so that no soldering is necessary and you can hide everything inside the large wiring harness.
I put a wiring method in C4 Tech Tips on hooking up the aux fan switch to drive both fan relays. You can get the clip on connectors from Radio Shack so that no soldering is necessary and you can hide everything inside the large wiring harness.
sure would like to read it ,,,,, if it were working
Burning Brakes
Joined: Jan 2002
Posts: 993
Likes: 4
From: Glen Burnie MD
Originally Posted by CFI-EFI
There was no need for an additional relay. Just hook the switch up to provide an additional ground path for the primary circuit of the stock relay. Also, if you lose track of the temps, the ECM and A/C will STILL kick the fan in when called for. It is as simple as a switch and two lengths of wire. You did WAAAAAY too much work.
[RICHR]
