Running a FMIC: Keeping it cool.

[SMG]

Since I installed a front mount IC on my car it's had a bit of trouble keeping cool. The 2.0 is supposed to run at about 190F and I was seeing 220F on a daily basis.

About a week ago I saw 230F on the temp gauge after a hard run and I knew I had to do something. I picked up a low-temperature fan switch. It's made by Meyle and the part number is 701959481. The stock fan switch turns the high-speed fan on at 215F and turns off at 203F. The low-temp sensor turns the high-speed fan on 200F and turns off at 188F.

The main problem I ran into was that my car came with a triangular connector like this one:



The cooler temperature sensors only come made for a square plug so obviously it isn't plug-and-play. I went to a junkyard and got a square connector and a few inches of wire for $10 and spliced it in. The connectors are almost the same and the wire colours are identical and in the same pin positions.





So after it was all back together the fans started coming on earlier and it was really nice to see the car keeping the temps under control. The FMIC causes the car to run warm most of the time but the car now only gets up to 210F in traffic and is dead-on 190F while cruising.

Awesome mod for only about $35 total!

[wawalker]

I agree that you needed to do something, but does this mean that once you are in traffic and the high speed fan comes on at 210F it never goes off again? even when you are just cruising and seeing 190F since it goes off at 188F? Perhaps something in between would be just a little better? Back in the day I had an '87 GLI that I ran the snot out of--the oil temps would get pretty high, so since it had an oil to water cooler at the oil filter just like these newer cars I put in a cooler thermostat and switch and it killed my efficiency--I went back. (In hindsight I should've put on an oil cooler.)

[SMG]

What it means is the fan comes on at 210F and turns off at 188F. With the fans off the car then settles back to 190F (where it wants to be) and then the fan comes on again when I've stopped and the temperature climbs to 210F.

This is the mildest low-temp fan switch you can get though so there's no real other option. The thermostat is the exact same temperature as the low-temp fan switch (188F) so there's no point where the two are working against each other.

So this isn't changing the running temperature of the car at all, it's only giving the car the ability to control its temperature with a FMIC.

[wawalker]

Originally Posted by SMG

What it means is the fan comes on at 210F and turns off at 188F. With the fans off the car then settles back to 190F (where it wants to be) and then the fan comes on again when I've stopped and the temperature climbs to 210F.

This is the mildest low-temp fan switch you can get though so there's no real other option. The thermostat is the exact same temperature as the low-temp fan switch (188F) so there's no point where the two are working against each other.

So this isn't changing the running temperature of the car at all, it's only giving the car the ability to control its temperature with a FMIC.

OK, so it cools it down to 188F and shuts off and then the temp goes back up to 190F while cruising--gotcha, makes sense. The first time I read through the 188-190 thing threw me off.

[SMG]

Bump for an upcoming summer season!

[Pseudotropheus]

That is an awesome upgrade. A little solder gun and some wires, and your good to go.

[SMG]

So I removed the AC completely, got rid of the condenser in front of the rad and now the car runs way cooler and doesn't get hot in traffic now at all!

I'm going back to the original temperature switch asap. With no condenser blocking the airflow there's no need for the cooler fan switch at all.

[raymondlee]

ac delete is a healthy upgrade