Should I Be Worried?

[MsRN]

I was driving to work this morning (0530), and noticed 20 minutes into the drive that my coolant temperature needle was barely flirting with the first 'hash mark'. It never reached mid-gauge in the forty-five minutes I drove the car. Ambient temperature was 52-58 degrees Fahrenheit.

On the way home tonight, I went into the hidden OBC functions, and turned on coolant temperature monitoring. The return trip was at 62 degrees Fahrenheit give or take, and coolant temp from ten minutes into the drive onward averaged 70C+/- 5C (rather cool by stock E46 standards--it should be 80-90C or so, if I 'member properly).

As some of you know, I am the proud new owner of an ESS twin-screw, intercooled supercharged ZHP (whew, try saying that three times fast!) Are these cooler running temps consistent with supercharging? Should I be concerned with the buildup of organic acids and moisture in my oil, and loss of TBN? Is the oil even warm enough to properly do its job?

Or--should I be concerned that the MAP thermostat is failing, and stuck open?

Oh, mighty ZHP Mafia brain trust, I seek your wisdom and guidance...

[johnrando]

First of all, very cool on the ESS. Didn't know that. Would love to hear how that turns out for you. Secondly, very much a guess, but it would seem to me like a thermostat issue, sounds stuck open. Outside of that, this is way beyond my knowledge, dealing with a supercharger. Hope it's something small and works out quickly for you

[Newjack]

I'm not saying I'm right here. But I had a similar problem right before I refreshed my engine cooling system. Turned out my thermostat was bad and was getting stuck open. It was taking my car way too long to get to the proper temperature. After the refresh, my temp floats quickly and calmly right up to the middle mark and stays there.

When was the thermostat replaced?

Also congrats on the new car! I'm super jealous of that supercharger...

[Gheybe]

I'll say as well you should check the thermostat. Replace it. It's like a 40 dollar part and really easy to do.

I had the same issue.

[kayger12]

Yep- thermostat has failed.

I'd replace the water pump, belts and pulleys while you're at it.

All 60,000 mile items to replace, and iirc, your ride has around 65k, correct?

Droid X. Tapatalk. Use it.

[kpro]

As some of you know, I am the proud new owner of an ESS twin-screw, intercooled supercharged ZHP (whew, try saying that three times fast!)
Or--should I be concerned that the MAP thermostat is failing, and stuck open?

eeeeeek! So excited for you!!! and very jealous too Did you buy a new ZHP or supercharge yours? ....and you are correct about your thermostat sticking open.


*edit* oh yeah, I forgot your other one was totaled. Congrats on the new car too!!!

[Ryans323i]

Whoa, point me in the direction of where you introduced your new car. Hope there's pics!

[danewilson77]

Good that it failed open though....hehe

[MsRN]

Yep- thermostat has failed.

I'd replace the water pump, belts and pulleys while you're at it.

All 60,000 mile items to replace, and iirc, your ride has around 65k, correct?

Droid X. Tapatalk. Use it.

The water pump was changed out at 32k miles, I think; I'll have to check the records. Fortunately, I just happen to have an OE thermostat and EMP Stewart water pump on hand...I never changed them out on my old ride.

Time for Rogue pulleys, though...I just don't trust plastic and constant thermal cycling!

IIRC--now I finally realize what that means...I feel so blonde...

[echo46]

I third or forth that the thermostat is stuck open. Happened to my on my e36 and the needle would not move. At least it didn't get stuck the other way.