Engine temp always reads 285.
 

I recently replaced the thermostat housing and I was still throwing codes (p0118 & p0128). I have used a few scan tools and all are saying my water temperature is 285 degrees. I'm not leaking coolant and there is no oil in the coolant. All fuses are good as well. I hope someone has some insight cause I'm at my wits end with this. I have only had my 209 clubman S for 4 months and have had nothing but problems. Love the car just want it to ride smooth.

P.S. the engine sounds rough all the time as well.

Shouldn't go much above 200 on a bad day. Are your fans working?

Mine always reads anywhere from 217-223. That's the safe bet to feel good about your car. Good luck man.

What's the condition of the water pump (main one, not the auxiliary covered by the recall)?

The fans are running constantly, even after the car is off. The water pump seems to be working fine, but I guess I can tear it apart this weekend and see if I'm missing anything. Today it seems to be lagging a bit when I accelerate. Not showing any signs of overheating though.

Coolant temp sensor has probably failed. I think there are many reports of that around here.

That is an abnormally high reading. Even with anti-freeze 50/50 mix in your car that would mean your coolant is boiling. Getting a coolant temp this high is pretty dang hard.

Your temp sensor is probably defective. The ECU controls fuel injection, boost, and spark timing based off many engine parameters INCLUDING engine coolant temperature. If you're getting a bogus reading it makes sense your car is running very rough.

I just changed out the coolant temperature sensor a few weeks ago, but I'm sure I messed something up. I'm going to replace the sensor again and hopefully that changes things. Thank you for all your help.

Let us know the outcome.

Update. I know its been awhile.since I posted. I'm in the marines and I move around a lot. I took the mini to the dealership and the replaced the wiring. Said it was wires wrong. They also replaced the head gasket. Fast forward to now. Throwing P1497 code. I replaced the timing chain tensioner Today. Car has been running rough for months. Doesn't want to start either. Can hear an air leak but I can not find the source. Saw a lot of post about valve cover problems. Any suggestions?

It would be really nice to know the outcome of this post. Just replaced my t-stat and eng temp reads 285, fan runs even when cool but car runs perfectly. Scanguage clears p0118 code then it comes back on restart. Thought I crossed t-stat wire and turbo wire but when i interchanged them there was no difference in code or temp reading. Any thoughts?

I don't know the temperature read on mine, but the problem is the same and I know it's not hot. Has anyone ever received resolution on this issue. Had the water pump replaced a month ago. Replaced the thermostat housing which came with the new sensor. Fan runs as soon as key is on and runs for10 min. After turned off. --- this is when starting cold! After a day of trying this and that ( mostly bleeding the system) with no different results, I put in the old sensor with the same results? I'm out of solutions. Could it be a defective sensor? What else could it be?

2009 mini S -- JCW

Did anyone find the solution for this issue? I have the same issue. Check engine light, coolant temp shows 286 degrees with scan tool while engine is cold. I can clear code with return on startup. New thermostat installed with same issue. No coolant leakage.

You might try resetting the ECU. You should be able to find the instructions on this forum.

Hi. Did you get any answers to this? I am experiencing the same thing. 07 S 80k miles, had for 11 years now. This is something new!!