I've seen millions of people with fan problems, most of them NOT blowing but mines continually blows no matter if the car is cold or warm from driving. Its killing my mpg's not to mention I've gone thru two fans from worn out bearings because of this. Can anyone give me advise on whats causing the fan to continuosly work without cycling?? And no it hasnt been directly wired or jumped in the connection housing to make it blow all the time. Please HELP!

 

Disconnect the thermal control switch and see if the fan goes off.
If it DOES go off then replace the switch.

If it DOESN'T go off, then replace the relay.

 

Have you tried disconnecting the switch on the back of the block? Or at least tried troubleshooting at all?

 

Damn ninjas... (4drEF)

 

WINNER WINNER CHICKEN DINNER!

 

Yes I have done trouble shooting. I didnt bother with the sensor on the back of the block because it isnt the two wire kind...it just has one wire coming out of the sensor. I've disconnected the relays for both fans with the key on, still the fan runs. I've disconnected the sensor on the head below the distributor and the sensor on the thermostat housing...fan still runs. I'm confused. I just swapped a jdm ZC motor and I used all my sensors from the old motor because I wasnt sure of the japanese specs on the sensors that came on the motor.

 

Pretty impossible for the fan to run without power so I fail to understand how the fan runs without the relay connected.

Also, the 2 wire connector may be located on your thermostat housing.

Check your BLUE wire on the fan and make sure it's not shorting to ground before the relay.

 

I think the one under the distributor is on it's own circuit so to speak (for the gauge cluster). The fan switch (back of the block) is basically an on/off switch specifically for the fan. When it gets hot enough it completes the circuit and turns on the fan. I don't know how you only have one wire, are you looking at the sensor for oil?

Edit: Unless yours is switched to the newer style (fan switch on thermostat housing) your switch should be here (green two prong, single prong is for oil)



If you don't have that plugged in and you don't have the newer style thermostat housing with the sensor on it you need to physically back track your wiring from the fan because as 4drEF stated, it's "Pretty impossible for the fan to run without power." It's getting power from somewhere...

 

Yes my engine is a 2000 model ZC...the only sensor on the back is the oil sensor. My first D15B(original motor) had the two prong sensor on the back but we directed the wires to the thermostat housing sensor years ago when i upgraded to a D16Y7 long block. With that particular motor everything worked as designed but the car has been sitting in my garage for almost 5 years before I decided to put the ZC in.

 

Just chcked for grounded blue wire...negative on that one. I probably shouldnt worry about it,not my daily driver just weekender car. Thanks for advise though guys.

 

So as it sits you have the switch located on your thermostat housing correct? If so, just do as "4drEF" and "N3va3vaSatisfi3d" stated and unplug it and see if the fan turns off. If it does, replace the switch.

 

I did that multiple times and even checked to see if something got lodged in the connector during the swap...nothing. fan kept blowing even while EVERYTHING was unplugged. The only thing that kills the fan is when i pull the fuse #15 from under the dash.

 

CRAZY!!!! Now I really want to know what's going on!!

 

How does this kill ur mpgs

 

Car runs cool, ecu thinks it should be running in enrich mode, thus dumping more fuel in unecessarily. Ergo, mpg droppage..

 

Winter - maybe... Summer - HIGHLY doubt it makes a BIT of difference. Electric fans only push so much air at any given time, unlike engine driven fans. If it were an engine driven fan I might agree, but given the circumstances... especially since the OP lives in Texas of all places. Now if you said something more towards causing the alternator to put more load on the engine - a touch more believable.

 

Follow that blue wire.
It's not making sense that you can run the fan motor with just "+" hooked up.

 

Its killing my mpg's because the motor is not reaching OPTIMAL temps...thus assisting the combustion process. I know my car...Ive had it for ten years and i also know that I USE to get over 300 miles a tank full and now its only getting like 260 or so. Believe me I know this car like the back if my hand but this issue has me stumped just like the rest of you guys!

 

I also know that while the car is moving the fan shouldnt come on unless Im runnin the AC which there is none, the compressor is still in the garage until i can find some R-12.

 

P.S. @ nevaevasatisfied...i never said it was running soley off the blue wire. Both wires are hooked up as they should be.

 

If you just swapped in the ZC, and have had this issue since completing the swap, then how do you know you should still be getting 300 miles to a tank? I mean, the engine is what uses fuel, not the car, so logically, a different engine will get a different number of mpg.

 

Exactly when did I say that you said what you say I said you said?

 

My bad, it was 4dEF...damn smartphone screen is only so big.

 

The ZC is the equivelent to an amercian spec D16Y7, just has a milder cam...which isnt gonna make a difference especially when my car never sees over 65mph. I didnt do DOHC swap,its the same whimpy SOHC.

 

My point was that just as 2 equivalent engines can vary in power output, they can also differ in fuel efficiency.