[D1A]

Hi all I am looking for input on an issue I'm having with poor acceleration.

The car seems to be in some sort of limp mode where the acceleration has dropped massively and when this happens I can hear the rad fan on max speed. Sometimes I get lucky and get a few minutes of normal operation but this is now basically constant. I was previously restarting the car several times to try and reset it to normal when in a pinch.

I had my independent mechanic take a look at the codes and he said that the temps were going up/down too fast but cleared it at the time as the car was working normally again. I since took it to a BMW dealership where they advised me that a code was coming up on the cylinder head temp sensor. I have since changed this but issues continue.

I am taking the car in soon to be looked at again.

I have monitored the temps which are within normal ranges but this may be because the car is working extra hard to reduce the temps to meet target temps.

My theory is that my mechanical water pump may be on it's way out as I previously had coolant leaks which can cause wear on the pumps due to lack of lubrication etc.

Any ideas of what to check next would be greatly appreciated!


TLDR=POOR ACELERATION+RAD FAN ON MAX./106K MILES/HISTORY OF COOLANT LEAKS MOSTLY RESOLVED/TEMPS NORMAL/NO WARNING LIGHTS/2016 M140i/B58