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1G Radiator Fan Question and Understanding

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1GASonny

5+ Year Contributor
53
6
Apr 4, 2018
St. Petersburg, Florida
Hey guys,

I've purchased someone elses headache of course and theres a lot of non - oem things to this car so I'm trying to have a better understanding of how it 'should' be.

Heres my one current question :

I've noticed that it has two aftermarket electric fans, both wired into the harness. They only BOTH go off when the temps reach to 219 / 220. Seems a bit high. Any suggestions to help keep temps cooler, run the wires differently? The stock location of any fuse box has been relocated under the headlight (weird) and I'm just trying to undo this f***ery.
 
1) Does the car have ecmlink? It's possible that ecmlink controls when the fans turn on/off but not a lot of people do this.
2) It's likely that previous owner hooked both fans up to a coolant temp switch (cts). When the cts hits a certain coolant temperature, it switches the fans on or off depending on how the owner set it up. You'll likely see the switch on the bottom of the radiator or on the thermostat housing as pictured. With all that being said, it's strange that the fans would be set for 220 on either setup I've described.
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1) Does the car have ecmlink? It's possible that ecmlink controls when the fans turn on/off but not a lot of people do this.
2) It's likely that previous owner hooked both fans up to a coolant temp switch (cts). When the cts hits a certain coolant temperature, it switches the fans on or off depending on how the owner set it up. You'll likely see the switch on the bottom of the radiator or on the thermostat housing as pictured. With all that being said, it's strange that the fans would be set for 220 on either setup I've described.
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That's what I thought. I've read once before that stock both fans kick on at 220. Yes I do have ECM Link but for the life of me I could not find the setting to change this. If I can where can I find it? Is there a way for me to correct this issue outside of link?
 
That's what I thought. I've read once before that stock both fans kick on at 220. Yes I do have ECM Link but for the life of me I could not find the setting to change this. If I can where can I find it? Is there a way for me to correct this issue outside of link?
I'm pretty certain the stock fans don't turn on at 220; Probably 190-205. Look under the fps tab on the left in ecmlink and see if there is something setup there. If you don't see a table of parameters, then it's not setup using ecmlink. I can't really tell you how to fix it if I don't know how previous owner installed it.
 
I would undo everything to do with the fans, and revert it to stock using factory schematics, that or allow Dsmlink to control it, there is no way that the factory had the fans come on at 10 degrees above water boiling temperature, its almost impossible on a hot day for the fans to bring the temp back down to normal once they are at 220 degrees other than shutting it off to cool or driving it down the interstate under low load.
 
Isn't the fan control only on 2g's through link? Go back to the stock fan especially the p/s. I've had the same issue in the summer with mishimoto fans. Had to trim the fan shroud and the tabs on the mishi radiator for clearance. Haven't had an issue getting above 215ish, but the weather was cooler when I swapped mine back.
 
That is genius. So all you have to do is run the ground on FPS harness to ground on temp sensor at radiator, then set the parameters under FPS in link?
Don't even bother with the temp/thremo sensor because that would be redundant. You'd be using a controller to control a controller that controls the fans :)
Yes, the fps acts as a ground for your fan relays. Ecmlink determines when your fps will send ground to the relay and turn the fans on.
 
Don't even bother with the temp/thremo sensor because that would be redundant. You'd be using a controller to control a controller that controls the fans :)
Yes, the fps acts as a ground for your fan relays. Ecmlink determines when your fps will send ground to the relay and turn the fans on.

So ground from FPS to ground on fan relay?
 
No worries, I'm going to be working on it later this weekend. Figured it was weird. Makes me want to return everything to oem wiring
 
I don't know of a way to let Link control the Fans in a 1G. For my 91 there is a connector right next to where the lower radiator hose goes into the radiator. The passenger side fan has a plug in the loom that plugs into that and brings that fan on around 206 ( as shown in Link ). To get the driver side fan on I press the A/C button on ( I don't have A/C ).
 
I am not sure if it is me only but it seems that people on tuners keep thinking that coolant fans should come up on at 190 and I will have to disagree. My comes to on at like 213 or somewhere in that neighborhood. Fan and switch are new Oem replacements. As a matter of a fact most cars on the road the fan comes on at that time or even later. I can post scan tool data of other cars and post a log of my car. But one thing for sure, something is wrong with the logic over here. And don't you dare tell me about timing. I logged my car for many years and I can not verify that at such low temp.
 
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I am not sure if it is me only but it seems that people on tuners keep thinking that coolant fans should come up on at 190 and I will have to disagree. My comes to on at like 213 or 215. Fan and switch are new Oem replacements. As a matter of a fact most cars on the road the fan comes on at that time or even later. I can post scan tool data of other cars and post a log of my car. But one thing for sure, something is wrong with the logic over here. And don't you dare tell me about timing. I logged my car for many years and I can not verify that at such low temp.
I guess it depends on what thermo switch you have then. When I used my thermo switch the fans came on around 195-200. I can't remember exactly. It aslo depends on where your thermo switch is located..... Here's some more logic: if the thermo switch is on the radiator and the temp sensor is on the thermostat housing...could that be the discrepancy in temp?
 
Mine is mounted in original location. It could be that my temp sensor is a bit old, about 29 years old so few degrees could be off from others but not 20 degrees off. Once it went over 225 and at that time I decided to replace the switch and the fan and went back to where it used to be. Either way if it is under 215 it is normal.
 
Hey guys,

I've purchased someone elses headache of course and theres a lot of non - oem things to this car so I'm trying to have a better understanding of how it 'should' be.

Heres my one current question :

I've noticed that it has two aftermarket electric fans, both wired into the harness. They only BOTH go off when the temps reach to 219 / 220. Seems a bit high. Any suggestions to help keep temps cooler, run the wires differently? The stock location of any fuse box has been relocated under the headlight (weird) and I'm just trying to undo this f***ery.

Your number one problem is aftermarket fans.
 
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