Hmmmm Fan always on....Questions guys

XxSlowpokexX

Registered User
Ok. So in my quest to figure out whats wrong with my car I decieded to run a dedicated power line to my spal fan. I used a bosch 75 amp relay,,,,I didnt really think anything of it...

But my fan comes on the minute a turn my key on. Its done that for awhile and its still doing it. I have the high/low fan power currently as the 12v source for the relay and power battery direct


Ok so does my fan comming on when I turn the key indicate something? It was doing this before I did the external relay but didnt think anything of it..... My cars still running like poop and was thinking this may be an indication of something bad such as my ICRM....And if that is the case..Could a bad ICRM cause me to run poorly?
 
Love the signature.

I think IRCM can cause problems, The fans run all the time when the AC is on. Just throwing that out there. Otherwise it should be triggered by the computer when it hits a target temp. Never all the time. Unless you are not cooling down to target off or your target off is too low it will just stay on till next time you turn on the car.
 
If the EEC goes into fail safe mode either because of an internal failure or 1 or more of the primary sensors are not working then the fan will run continuously as well as a major rich condition with retarded timing... and that assumes a stock setup with stock injectors etc ;).

Fraser
 
you may have the same issue that I chased for a year. My IRCM shot and and took out computer and that in turn took out tps and a couple other sensors. It took me forever to figure it out. Finally I swapped out the EEC, IRCM, and the other sensors. I found out about the TPS when on the dyno... Cant remember what year your car is but mine is a 90 and we found out there is a supply of power to the EEC through the IRCM. It must of spiked and shot it and the 5v supply...
 
Oh and my car ran like Doo Doo. Once I swapped those out I took it out in front of the house and hammered it. It got all kinds of sideways and ran like a raped ape then... I fought it for over a year changing out wiring harnesses, dashes, and finally did the swap and it solved my issue. I havent heard of anyone else having the issue I had and this sounds just like it...
 
Crap. If it could be the ICRM Im going to flip. I dont think I had the AC on. It does it immediately even when cold. Im spending tomorrow on it.

Now the EEC and chip hd both been replaced with spares I had..Same issue. Reburnt chip from my tune file. The one DD had..No difference

But it totally seems like Im running on no tune. And with 60lb injectors 90mm LMA cam heads etc etc..no tune means poop

Now primary sensors are MAF, Crank sensor, Cam sensor and tps Maybe??? I had checked all of those......And even after checking out ok I replaced them all anyway!

Now on a 94-94 what exactly does the ICRM control? If that could potentially be an issue Ill try a used one and see what's up.

Thanks everyone

This car is going to kill me....
 
so insted of coming here and swapping parts out, you rewire your fan thinking that may be it ? OOOOOOOOOOOOOOH BOYYYYYYYYYYY
 
I know what our going through! I chased mine forever. Thought it was a ground off somewhere. Thats when I started chasing the wires and found some splices and then swapped out wiring harness both inside the car and under the hood.
 
so insted of coming here and swapping parts out, you rewire your fan thinking that may be it ? OOOOOOOOOOOOOOH BOYYYYYYYYYYY

No I did the external relay because the fans like to burn up fuse boxes. I did that while I was swapping heads and installing Meth kit etc. Swapping parts out isnt th ewayto do it. You check the part to se if its bad. I swapped out parts for known good ones out of frustration because everything checked out good yet the car still ran poorly.

Now the ICRM I did not swap out and i dont have a spare one to just check out that I know works...And I know yours may potentially have issues as you did something to make your fans not work at all. So Id rather not try that one
 
I would swap out the IRCM. We found one sheet on the schematics that showed it having the 5v reference and then the feedback went to the EEC... Sounds like you have the same issue that I did..
 
Rico..Voices in my head involve that DIsco Enferno song...

Anthony I just looked through my Ford hop manuals and there definitely is a 5v source to EEC from ICRM....So it very well could be. my next step before bringing it to my buddies shop to do some testing..Hopefully its not mechanical
 
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