E90 error code 27E4

[mv312r]

After recently replacing one of the infamous throttles actuators on my 2008 E90 M3 that caused code CDC0 among others + a huge light show on the dash I'm still getting occasional 27E4 code (reading these with BT dongle + iViNi Android app) with associated crawl mode. This error condition usually happens if I cold start the car and start driving without warming the engine too much. Also happened once or twice with warm engine if I start driving pretty much immediately after starting the engine. If I let the car idle for a minute or two driving it no codes/errors.

I read from the forums about potentially fried/shorting vacuum valve sensor so I bought the new vacuum line with sensor, but we only changed the sensor so far as changing the line is a lot more work but this did not help. I cannot say I'm hearing any whine from left front of the car as was suggested in some other thread, but I have Supersprint slip ons on the car that make decent noise even on idle and maybe I cannot listen this thing properly.

I've pretty much lost my faith on the big authorized BMW repair shop I previously used; with throttle actuator problem they 1st nuked my Evolve tune just in case (I gave them ok to do this since they suggested it would help) and then started talking about ECU replacement; I only got the code reader at this stage and somewhat forcibly told them "it's the throttle actuator". No more throttle actuator errors since then. I'm currently working with a smaller repair shop, nice and skilled guys but not much experience with M3s as these things are hugely expensive and thus very rare here.

Here's the Error codes from code reader app.

Motor Control:
Engine / Motor
Code: 27E4
Code: 2B57
Code: 2796

Here's the link to the main code 27E4 description, to my understanding the 2B57 and 2796 are kind of hangarounds that indicate the limp mode has been initiated and engine failure reported.

http://www.m3post.com/forums/showpos...7&postcount=17

Any thoughts on what next? I'm tempted to think this is caused by vacuum line leak that gets fixed be thermal expansion once the engine is properly warmed and I should replaced the vacuum lines that came with sensor too. But then again I'm quite clueless when it comes to cars so I'm purely quessing here. I've got 70000 miles on the car, no warranty and I'm kind of tired with the repair shops that almost blindly seem to come up with what expensive part to change next while charging hourly rate to come up with the ideas. And there is zero of negotiating any "no charge if changing part XZ does not help" over here

[///mawana]

This might help: http://www.m3post.com/forums/showthread.php?t=310475

[TanDaMan]

Bring thread back to life since I have been getting this code after replacing throttle actuators and then replacing O2 sensors. Puts the car in limp mode at start up but when I turn it off and restart it limp mode disappears. I have a 2010 m3. Searched everywhere already.