My 2004 M3 has always had the Mishimoto electric radiator fan kit, it's single speed using the kit's controller with manually set kick-on temperature reading from the included probe sitting close to the radiator inlet from the engine hot side. I still have the factory front pusher aux fan as well. Now my car's cooling has given me fits as I started tracking more over the last couple years, so this is another topic that I need some insight in. My car's coolant temp on the streets when not being pushed or under heavy load seems to sit around 185-195F, going off the OBDII readout (and needle sits 12 o'clock center). I used to have the fan kicking on around low 170s F (due to my fear of my car running too hot or overheating as I had issues on the track running too hot, still do somewhat) it would actually keep the temps under 185F and preventing the coolant gauge needle from hitting 12 o'clock center unless I start driving the car harder, keeping the car from properly fully warming up.
So I've since raised it to kick on around 190F, and just driving normally on the street without pushing the car the electric fan doesn't even need to kick on and temps still stay around mid to high 180s on the street. I figure this is the right way to set an electric fan, since doesn't make sense having the fan running if say cruising on the highway and having plenty airflow (I imagine that's how the factory clutch fan operates).
BUT, I have noticed the factory front pusher aux fan seems to be running often, it's quiet so makes it hard to tell when it kicks on but its on fairly early before the car is even fully warmed up (needle still below 12 o'clock center), so is this normal and expected? All my observations have always been with the A/C off as well. Or is the cars computer expecting a mech fan to be running and thus thinks there is a cooling issue and kicks on the aux fan early? So basically how should one be setting the electric puller fan to kick on with its single speed temperature setting on these cars?
So I've since raised it to kick on around 190F, and just driving normally on the street without pushing the car the electric fan doesn't even need to kick on and temps still stay around mid to high 180s on the street. I figure this is the right way to set an electric fan, since doesn't make sense having the fan running if say cruising on the highway and having plenty airflow (I imagine that's how the factory clutch fan operates).
BUT, I have noticed the factory front pusher aux fan seems to be running often, it's quiet so makes it hard to tell when it kicks on but its on fairly early before the car is even fully warmed up (needle still below 12 o'clock center), so is this normal and expected? All my observations have always been with the A/C off as well. Or is the cars computer expecting a mech fan to be running and thus thinks there is a cooling issue and kicks on the aux fan early? So basically how should one be setting the electric puller fan to kick on with its single speed temperature setting on these cars?
Comment