2011 X5 35i N55 - intermittent starting + CEL on WOT

[bmwannabe]

Originally Posted by ard

Good luck with this.


Asking people 'how do I halfway fix a car' is always a mess

I pick my battles perhaps with a different mindset. at 11+ years old these cars are far from perfect - and thus far I fail to see a direct correlation between the car intermittently not starting, and the valvetronic issue that is present ( not saying there is 0 correlation as i know there is a DME firmware update that impacts the off position of the valvetronic and helps with starting) - so I suspect this issue is elsewhere.


Battery was replaced about 2.5 years ago. HPFP and Valve cover gasket + valve cover were replaced within the last year. Also repaired a snapped starter ground wire that caused a similar issue a few months ago.


I've narrowed it down to:

1. Wastegate actuator ( boost solenoid ) due to 2C57
2. failing battery or alternator.

open to suggestions


TIA

[bmwannabe]

update: I might have resolved the 2C57 error


2C57 - Charging pressure control, plausibility Pressure too low - happens at high boost / or WOT.


I suspected this to be the boost solenoid - but I found the long braided vacuum line disconnected from the solenoid and plugged it back in. After this I drove it pretty heavily and didn't see any CEL on during WOT.


This still leaves the intermittent failure to turn on which also happened again today. Here are all the codes along with my comments ( most don't come back after clearing )


2BEB - Mixture control: Fuel-air mixture too rich,large deviation.
2E0F - Valvetronic deactivation (DME update might fix)- https://www.babybmw.net/threads/2e0f.../#post-1372272
2D42 - 2D42 - Valvetronic, adjustment range: stop not learned - https://www.bimmerfest.com/threads/2...e-n55.1411776/
2DCE- Valvetronic isn't functioning as expected, but the DME doesn't exactly know why
2E0F- Instances of 2DCE have occured enough times that the DME disabled Valvetronic and enabled throttle body control
2DCF- No Movement Identified in Valvetronic - could be DME or Harness

2EFE - Misfire - several cylinders damaging to catalytic converter or damaging exhaust gas
2F03 - Misfire - cylinder 5
2EE0 - Combustion misfiring several cylinders - Fuel Injection Deactivation
2EFF- Cylinder 1 Misfire Detected 2EE0 - Combustion misfiring. several cylinders: Fuel injection deactivation
2EE4 - Combustion misfiring, cylinder 1: Fuel injection deactivation
2EF1 - Combustion misfiring, cylinder 5: Fuel injection deactivation
2F00 - Cylinder 2 Misfire Detected
2EE7 - Combustion misfiring, cylinder 2: Fuel injection deactivation


2C57 - Charging pressure control, plausibility Pressure too low ( Happens when on WOT ) Vacuum pipe was unplugged

A10A - Exclamation mark on dash ( TPMS? ) ( battery voltage too low ? )



Links above are to E90 335i with the N55 engine and my findings are quite similar.