[rismo]

My car has been towed away today... After a dinner this evening. I drove away and noticed that my radiator fan was blowing full speed (Engine was completly cold) while driving out to the highway I noticed that especially in the midrange the car lacked torque. I switched to map0 and continued normal driving (100km/h - 60mph/h) after a while the cooleant temp warning in the dash lighted on.
This was a bit strange as I did not speed and the oil temp was still low. (around 100 degrees celcius)

After I slowed down to 70-80km/h the warning went away. 5 minutes later it came back and was shortly followed by a warning to stop the car immediatly because of overheating.

I did not had my laptop with me so I could not scan. But my Iphone OBD2 reader gave me no error codes. Same on the device of the engineer that towed me away, no codes.

We checked for oil in the cooleant but it was clean. We did detected some noticable steam/water at the exhaust pipes. But this could also be weather related.
Oil and water levels are checked and ok.

My dealer will dive into it. But just wondering what could this be?

Any suggestions or similair experience?

I do have recently installed my PMW meth kit with chargepipe and I'm driving around without engine (bay) cover(s), could it be a sensor thing(I hope)?

[vase330]

Could be malfunctioning thermostat?
3yrs ago when my car had less the 15K miles on, I had some sort electrical failure that apparently prevented my fan among many other components from turning on. Anyway this resulted in over heating induced limp mode. Guess what, the oil temp never climbed past 250F but when I popped the hood I was hit in the face by a heat wave coming from the engine bay. The engine was nasty hot! Other folks who have had radiator failure also noted the oil temp means nothing. You can still severely overheat with your oil remaining starkly normal.

[samchoi604]

water pump

[tibra1]

Originally Posted by samchoi604

water pump

+1..on top of everything else with this car apparently there is a weakness w the water pump..i know 3 guys who have had to replace theirs and they were all low mileage cars.

[vase330]

Right! I forgot its all electric and apparently a weak link on the N54/N55. No first year model BMWs for me going forward. I'll wait for the new M3 after the bugs get worked out.

[rismo]

And the winner is SamChoi.... waterpump...

And my hpfp is also in the proces of leaving this planet...

Pumps and BMW = No go.... pfff 80000 euro car....