[N13Enjoyer]

Good day,

I have a BMW N13 motor that has about 62000km on the clock. I have been running a stage 1 OTS tune, but the car would periodically go into limp mode which lead me to handing it off to the mechanics for investigation.

Apart from the cam timings that was out and a leaky air intake hose that got replaced, the also found the cylinder pressure, especially in cylinder 3 was higher than usual, the then continued to scope the cylinders and found no carbon build up, or damage to the walls (as would be expected in this fairly low millage engine) and basically ended up telling me they don't know what to do about the situation as they even checked the pressure on a much higher millage N13 that did not have problem. The flashed the stock tune and said at least it will run without warning lights on the stock tune, however the knock sensor readings are still pretty high during "at speed, low rpm cruising" (90kmph at about 1800-2200 rpm).

The exhaust valve has been checked and is not holding any excess pressure either (which can apparently lead to higher cylinder pressure).

The pressure readings they gave me was as follows:

Reference higher millage N13 motor:

Cyl 1: ~11 bar
Cyl 2: ~10.5 bar
Cyl 3: ~10.5 bar
Cyl 4: ~10 bar

My N13 motor:

Cyl 1: ~12.8 bar
Cyl 2: ~13 bar
Cyl 3: ~13.5 bar
Cyl 4: ~13 bar

Has anyone encountered the same problem perhaps? I have searched far and wide to find an answer, or at least some data to direct my money... i mean efforts in the correct direction.

Any response is greatly appreciated