nebulight

My fan won't turn on and my car is overheating in city traffic. I checked fuses and they are fine. I'm using a stock P72 OBD2a ECU right now until I get tuned, but I never had any issues until I installed this fan. I know the fan works because I hooked it up to my battery during the install to find out which wires would make it a puller fan. Any idea, or what temp the stock ecu will turn the fan on?

dpetro1

sounds like the thermo switch to me. its located in the thermostat housing. since you know the fan works, you can unplug the harness from the sensor and jump it. if the fan turns on than you want to replace the thermoswitch. if not it could be the fan relay.

nebulight

It's raining out now, but I'll check it when it dies down.

631 Teggy

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dpetro1 &raquo;</TD></TR><TR><TD CLASS="quote">sounds like the thermo switch to me. its located in the thermostat housing. since you know the fan works, you can unplug the harness from the sensor and jump it. if the fan turns on than you want to replace the thermoswitch. if not it could be the fan relay. </TD></TR></TABLE>

Yep. They'll take a **** every now and then.

nebulight

Just to be sure, it's 12 that I need?

TURBOFTW

iTrader: (1)

Yes, Is the thermostat new? It could be bad

If you want to test the switch unplug sensor number 12 and use a piece of wire and jump the connection it should turn the fan on when the key is turned to the acc position....

nebulight

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TURBOFTW &raquo;</TD></TR><TR><TD CLASS="quote">Yes, Is the thermostat new? It could be bad

If you want to test the switch unplug sensor number 12 and use a piece of wire and jump the connection it should turn the fan on when the key is turned to the acc position....</TD></TR></TABLE>

I jumped the connection with the key turned over to where it was beeping with the door open, and nothing. So I can assume it's the thermoswitch?

TURBOFTW

iTrader: (1)

Oops just read..lol the switch is fine the fan shouldve turned on if you did in fact jump the connection and turned the key on, try starting it with it jumped...

Mugencrxsir1

I had the same problem with summer driving, and I installed a toggle switch so I can just flip the switch on when sitting in traffic. If you can't figure it out, just running a toggle switch.

nebulight

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mugencrxsir1 &raquo;</TD></TR><TR><TD CLASS="quote">I had the same problem with summer driving, and I installed a toggle switch so I can just flip the switch on when sitting in traffic. If you can't figure it out, just running a toggle switch. </TD></TR></TABLE>

My problem with that is I will most likely forget about it while driving so I'd rather have my ECU control it, plus I only want it to come on when it needs to so I don't wear out the fan early.

Anyway, when the car does overheat, I just turn my heat on and it goes back to normal.

dpetro1

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TURBOFTW &raquo;</TD></TR><TR><TD CLASS="quote">

If you want to test the switch unplug sensor number 12 and use a piece of wire and jump the connection it should turn the fan on when the key is turned to the acc position....</TD></TR></TABLE>

try doing this with the car running, just to make sure. if you jump the switch and the fan does not come on than it could be the relay in the under hood fuse box. also as turboftw mentioned, are you sure the thermostat itself is working? (both hoses are equally hot)

nebulight

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dpetro1 &raquo;</TD></TR><TR><TD CLASS="quote">

try doing this with the car running, just to make sure. if you jump the switch and the fan does not come on than it could be the relay in the under hood fuse box. also as turboftw mentioned, are you sure the thermostat itself is working? (both hoses are equally hot)</TD></TR></TABLE>

Well, I jumped it and the fan turned on and I checked all the fuses and they were good. And when the car overheated one time, I pulled over and the fan was not on. I'm pretty sure it's the thermoswitch, so I just ordered one today from HPU. I did not check to see if the thermostat was working, should have done that but meh.

ProjectBoosted

iTrader: (1)

I just hard wired my fan to a switch i mounted inside my car ( i had a really thick aftermarket rad. and it would keep my car so cold vtec wouldnt cut on so i just turned it on when i needed it)

nebulight

Well, I'm using Neptune, so I should be able to have my tuner lower the VTEC engagement point.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HRTuning.com &raquo;</TD></TR><TR><TD CLASS="quote">VTEC Temperature Threshold Disable - Allows VTEC to activate while the car isn’t fully warmed up</TD></TR></TABLE>

Mugencrxsir1

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nebulight &raquo;</TD></TR><TR><TD CLASS="quote">My problem with that is I will most likely forget about it while driving so I'd rather have my ECU control it, plus I only want it to come on when it needs to so I don't wear out the fan early.

Anyway, when the car does overheat, I just turn my heat on and it goes back to normal.</TD></TR></TABLE>

You should'nt have a problem overheating when driving if you have a properly sized radiator. I never need a radiator fan unless I'm sitting in traffic for more than 5 mins in heat greater than 90 degress. That's why I chose the toggle switch
I just watch the temp guage when sitting in traffic.

nebulight

Yea, like I said in the original post, the car never overheats unless I'm in city traffic. I'm using a half rad civic style rad that's almost 2.5 inches thick, so driving isn't when I over heat, it's when I'm at a stop for a while. But I'm going to get tuned at Evans, and can't really get dyno tuned with an overheating car on the dyno.

Cyber ITR

sorry to hijack ur topic
but my car having similar problem, the fan only working when i turn on the A/C

any idea why ?

nebulight

Well, got the fan to turn on after a while, I had to switch my rad, and didn't bleed the coolant last time. But let some air bubble out, but now I have a bigger problem. When I let the car sit, I let the coolant temp rise up to around 180ish (trying to get the fan to turn on), then I'd give it some gas, and the temp would drop down to around 120-140.

Could I have a blow head gasket? The oil looks fine and so does the coolant, and there is no smoke coming out of the exhaust. The car no longer over heats, I sat in the car after work tonight to see if it would overheat, but instead the fan finally kicked on. Any ideas?

nebulight

Bump

mike1114

iTrader: (1)

180F is normal operating temp. If thats what you got, then your good.

You can just jump the ran to run all the time when the key is turned on.

I have mine jumped so it runs all the time, fully built turbo in Hot *** Florida, needs it.

Sitting at idle and driving around town in stop and go traffic are two completely different things. Drive around a while and make sure everything is ok.

nebulight

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mike1114 &raquo;</TD></TR><TR><TD CLASS="quote">180F is normal operating temp. If thats what you got, then your good.

You can just jump the ran to run all the time when the key is turned on.

I have mine jumped so it runs all the time, fully built turbo in Hot *** Florida, needs it.

Sitting at idle and driving around town in stop and go traffic are two completely different things. Drive around a while and make sure everything is ok.</TD></TR></TABLE>

I agree that it's normal temp, but why does it drop sometimes 60 degrees when a little gas is given? Is that normal?