I have a phase 1 EJ22 swapped in my 86 BRAT, and I'm not sure my electric fan is working. I used the radiator from my donor Legacy, with a Flex-a-lite electric fan mounted as a pusher configuration, on a Bosch style relay. To switch the relay I used the 'radiator fan' wire coming out of the ECU (F47-17), which should get 0V when the fan is supposed to be on and 12V when the fan is supposed to be off, so I fed an ignition switched power wire into the relay pin 85, and the relay pin 86 goes to F47-17, which the ECU should ground when the fan is supposed to come on.

 

For the temp gauge on my dash, I used a 255Ohm resistor in parallel to the thermometer wire to recalibrate the EJ22 thermometer to work with the EA81 gauge, as suggested by reading on this forum. The gauge now reads just under half during normal driving with airflow through the radiator, and will climb to near the top after 10-15 minutes of idling. But my fan never switches on, and I'm not sure if I'm just chickening out before it gets hot enough or if it really isn't working. So, how high above the normal driving temperature should the car get before the fan switches on?

Since not all swaps are the same, it's hard to say what your gauge should be reading. The best thing to do would be to figure out the actual engine temperature, then you'll know how the gauge reacts, what's normal and what isn't normal. If it's an OBD2 swap, just use a code reader to figure out the temperature. If you don't have a diagnostic port get one of those thermal guns and point it at the metal coolant outlet pipe on the top of the engine. this will be a fairly accurate engine temperature. Anything about 210 you should have fans running, I wouldn't be happy to see over about 220 while sitting and idling. In an ideal world, your temps should probably stay under 200.

Since not all swaps are the same, it's hard to say what your gauge should be reading. The best thing to do would be to figure out the actual engine temperature, then you'll know how the gauge reacts, what's normal and what isn't normal. If it's an OBD2 swap, just use a code reader to figure out the temperature. If you don't have a diagnostic port get one of those thermal guns and point it at the metal coolant outlet pipe on the top of the engine. this will be a fairly accurate engine temperature. Anything about 210 you should have fans running, I wouldn't be happy to see over about 220 while sitting and idling. In an ideal world, your temps should probably stay under 200.

says he swapped in a 2.2 that is phase 1, so would not be OBD2 equipped, so code cannot be read. Agree with you that the actual engine temperature needs to be determined. Swapped in motor with after market cooling parts, and rigged in resistor can't be relyed on to create an accurate temp gauge reading. Seems strange that the fans never come on. Something is not right about this. Are you sure the fan is getting power??

I know the fan is getting power because I can jump a ground wire onto pin 86 on the relay and the fan kicks on, it just seems to never get that ground signal from the ECU. Getting one of the laser thermometer guns is a good idea, then I'll know what my actual temperature is for when the gauge is reading high.

Fans should kick on around 204°F. Should stay on until back down to 194°.

 

Make sure the temp sensor for the computer is changing resistance as the engine warms. Its common for those to fail and tell the ECU its -40° all the time.

Go and buy a $20 mechanical water temp gauge (they have the probe attached and come with brass adapters) from local parts store (I'd add an oil and vacuum gauge too to make sure everything is OK) and you'll know how hot is getting under a load. While you are at it, grab an indicator light and wire that into the circuit, and you'll know if the fan is actually kicking on or not w/o fussing about.

 

To verify the gauge is accurate, stick the probe in hot water and heat it only within it's working range and use a turkey thermometer to monitor water temps and compare they are showing the same values.

Edited October 21, 201510 yr by Bushwick

For the record (because I hate when I search and find a thread and there was never any posted resolution), I finally got an IR thermometer and confirmed the fan was not kicking on when it should. Rather than try to track the problem down, I just bought a $15 adjustable aftermarket thermoswitch, let the engine heat to 200F degrees, then set the thermoswitch adjustment for that temp.

My dash gauge reads about half range at 200F degrees.

You should probably have the fans come on before 200 degrees, it's a 180 degree thermostat, so 190 degrees would be a good setting.

Okay, will do.

EJ 22 should run 190-195 normally. Set at 190° the fan will never turn off.

Set it for 200° and you should be good.

Huh, mine always run at about 180-185 when I'm driving, as checked by the scangauge. The fans kick in around 190 or maybe a bit above when I'm stopped (and AC isn't running, obviously).

Might be possible some of you have different thermostats? Some cars have various temps available and it's possible a different temp thermo was purchased w/o realizing. If you live in the desert or really hot/miserable (muggy) areas like Florida, running a cooler thermostat might be preferred and all-season cars or really cold winters benefit from a warmer thermostat as it'll help provide more heat (a 10 degree difference in thermostats can make big difference) provided the fans are not on constantly.

 

On newer cars, it's not as simple as many check the heat up time and compare that to the predetermined heat up time and will throw codes if it takes too long i.e. a "hold open when fails" thermostat will cause the engine to NOT reach desired temps fast enough or at all if it fails open. (ask me how I know)

 

BTW, do NOT buy those fail open thermostats, they are junk. Went through 2 of them in under 2 years on my Saab, and of course it's one of the ECM's that check for that. 

Edited November 6, 201510 yr by Bushwick

I only buy OEM subaru thermostats from the dealer. They aren't very expensive and the aftermarket ones cause all sorts of issues.

On a recently purchased 97 Outback, the fans are not kicking on.  How important is for them to run?

On a recently purchased 97 Outback, the fans are not kicking on.  How important is for them to run?

Start a new post and ask there. Someone will respond. This forum is very good about people responding.

I did find them kicking on finally.  So they are working.  The last owner gave me a set of old ones, I don't know why.