[KyleS]

Hi all,

First time posting. Hope I am posting in the correct forum. I've searched everywhere and I'm at a dead end. My car has been going into limp mode and has long cranks when starting.

Car:
2007 335i N54
JB4
MHD Backend
BMS DCI
Upgraded charge pipe w/ Tial BOV
Upgraded FMIC
Catless DP's
119,000 miles

I've owned the car for about 15,000 miles. Car was bone stock when I purchased it and was well maintained. 2 weeks ago the car unexpectedly went into limp mode while driving. The car started and drove normal the next day for ~20 min. While sitting in a parking lot the car shuddered, nearly stalled and lights came on indicating limp mode. I scanned the car with the Carly app.

Codes
3100: Boost pressure control shutdown
2D56: DME, internal error: Monitoring idling control (Note: this code has not
been recurring)
2A94: Crankshaft sensor signal

The car would now have long cranks when started and would stay in limp mode. After researching I decided to replace the crankshaft sensor signal. I changed the sensor last week and the car immediately started and ran like normal. Drove the car ~5 miles to go on a hike. Car started normal after the hike. On the way home, accelerating from a stop, the car stuttered and lights came on. It jerked the car pretty hard, felt as if i dropped the clutch without giving it power. Re-scanned the car and got the same codes, 3100 and 2A94 (Did not get 2D56). Frustrated, I searched all over again and found someone with a similar issue did not have their new sensor fully seated. I went out to go check and fired up the car but it turned on like nothing happened. Since then the car starts and drives like normal but goes into limp mode after about 20 minutes of driving. The car has no issues with WOT before it goes limp. Nothing particular seems to throw the car into limp mode except time.
My next step is to clean the VANOS solenoids. Research is pointing that it might be the cam bearing ledge, however, most people experiencing that are getting codes related to VANOS solenoids and go into limp mode after an agressive pull.

I'm stuck on where to look next and would appreciate any guidance or feedback. Thanks

Update:
Drove the car around town today and picked up a liter of oil to top it off. Wasn't sure if the oil could possibly contribute. Since the last oil change (about 6 months ago) it has gradually dipped to halfway between the min and max on the meter. Popped the hood open and was getting white smoke from the passenger side. Possibly near the downpipes. Continued driving and got the oil temp to ~200 F and got the same stuttering followed by limp mode. Parked the car and cleared the codes. Started up normally after it was cleared.

[KyleS]

Adding to my post with a log of the car stuttering and going into limp mode. Added a marker where I believe it started. You can see the RPMs blip up without pedal input. https://datazap.me/u/kylesebo/limp-m...data=1-5-10-17

[Stealthflipboy]

Originally Posted by KyleS

Hi all,

First time posting. Hope I am posting in the correct forum. I've searched everywhere and I'm at a dead end. My car has been going into limp mode and has long cranks when starting.

Car:
2007 335i N54
JB4
MHD Backend
BMS DCI
Upgraded charge pipe w/ Tial BOV
Upgraded FMIC
Catless DP's
119,000 miles

I've owned the car for about 15,000 miles. Car was bone stock when I purchased it and was well maintained. 2 weeks ago the car unexpectedly went into limp mode while driving. The car started and drove normal the next day for ~20 min. While sitting in a parking lot the car shuddered, nearly stalled and lights came on indicating limp mode. I scanned the car with the Carly app.

Codes
3100: Boost pressure control shutdown
2D56: DME, internal error: Monitoring idling control (Note: this code has not
been recurring)
2A94: Crankshaft sensor signal

The car would now have long cranks when started and would stay in limp mode. After researching I decided to replace the crankshaft sensor signal. I changed the sensor last week and the car immediately started and ran like normal. Drove the car ~5 miles to go on a hike. Car started normal after the hike. On the way home, accelerating from a stop, the car stuttered and lights came on. It jerked the car pretty hard, felt as if i dropped the clutch without giving it power. Re-scanned the car and got the same codes, 3100 and 2A94 (Did not get 2D56). Frustrated, I searched all over again and found someone with a similar issue did not have their new sensor fully seated. I went out to go check and fired up the car but it turned on like nothing happened. Since then the car starts and drives like normal but goes into limp mode after about 20 minutes of driving. The car has no issues with WOT before it goes limp. Nothing particular seems to throw the car into limp mode except time.
My next step is to clean the VANOS solenoids. Research is pointing that it might be the cam bearing ledge, however, most people experiencing that are getting codes related to VANOS solenoids and go into limp mode after an agressive pull.

I'm stuck on where to look next and would appreciate any guidance or feedback. Thanks

Update:
Drove the car around town today and picked up a liter of oil to top it off. Wasn't sure if the oil could possibly contribute. Since the last oil change (about 6 months ago) it has gradually dipped to halfway between the min and max on the meter. Popped the hood open and was getting white smoke from the passenger side. Possibly near the downpipes. Continued driving and got the oil temp to ~200 F and got the same stuttering followed by limp mode. Parked the car and cleared the codes. Started up normally after it was cleared.

Did u fix this problem?