[msall]

Hey, Guys

Recently my car (2007 335i - Stock - Automatic) has started producing the dreaded reduced power half engine light. This usually happens when I am sitting at a red light, going down hill (off the gas), or coasting. The light comes on and the rpm's start jumping from 1000-1500 every second. The gas pedal is completely unresponsive and the only way to fix it is to pull over and restart the engine. This happens almost every time I drive the car.

Codes I've received so far:

2F0C:
2F0C intake air temperature, signal: gradient
Error will cause an error light
Error is not currently present
Test conditions have been completed

2D58:
2D58 DME digital motor electronics, internal failure: control nominal torque?
EXPLANATION: Not a tuner detection code
FIX: Delete or ignore

Things i've replaced so far in order to attempt repair:
New battery
Replaced both TMAP sensors (Manifold and Chargepipe)
Standard PCV with RB PCV

Video of the behaviour

Any ideas?

[msall]

I ended up taking the car into the dealership to have it diagnosed. After 4 days they did not seem to have much of an idea either. They recommended replacing the DME, which according to there master tech might fix the problem. I ended up bringing the car home and started looking into the cold side of the turbo. I noticed a lot of oil in the charge pipe and intercooler. I cleaned all of it out and drove the car for a few days without the error recurring (approx 150km). On my way to work last Thursday it started again. I once again tore off the charge pipe to find oil in the charge pipe. My new OCC is bone dry so that leaves just the turbo valve stems as the culprit. Could heavy oil build up cause the tmap sensor to malfunction? I know some oil in the chargepipe is normal.

Things i've changed since my last post.
- Added Mishimoto OCC
- Changed the valve cover gasket
- Had alternator tested (tested good)

[Spacecpe]

did you check the wiring to the sensors ?

[msall]

So I thought I would update this thread just in case someone else ever encounters a similar issue. After taking the car to 4 different shops, everyone seemed to be on board with my local BMW dealerships diagnosis (new dme). Before I was supposed to drop the car of at the dealer, I plugged in my laptop one last time. I analyzed the sensor outputs for about 40 minutes at idle with ISTA/D. I noticed the coolant temperature would get up to about 70 degrees celsius and start fluctuating +/- 20 degrees. I replaced the sensor and the car has never driven better. It fixed my rough idle, random half engine light, and stalling. The car never once through any codes for this sensor. Fuel economy has also increased.

[Boland01]

Good for you. Your persistence saved you about $3K for a new DME! Thanks for the update.

[musa]

I had somewhat similar issue (same symptoms) but the code was 5E19 and would happen on WOT and when car has warmed up. It appeared to happen more often during summer. In my case the solution was to replace DME and the DME cooling fan (cost +installation around $1,500). I got the DME at cost value at a dealership. I was very lucky.

[musa]

Originally Posted by msall

So I thought I would update this thread just in case someone else ever encounters a similar issue. After taking the car to 4 different shops, everyone seemed to be on board with my local BMW dealerships diagnosis (new dme). Before I was supposed to drop the car of at the dealer, I plugged in my laptop one last time. I analyzed the sensor outputs for about 40 minutes at idle with ISTA/D. I noticed the coolant temperature would get up to about 70 degrees celsius and start fluctuating +/- 20 degrees. I replaced the sensor and the car has never driven better. It fixed my rough idle, random half engine light, and stalling. The car never once through any codes for this sensor. Fuel economy has also increased.

By the way, you're referring to this part, no?
Part number 13621433076 in diagram below (#7)
http://www.realoem.com/bmw/enUS/show...67#13621433076