Limp Mode: Need a little help

[e9xm3]

those codes are for, dsc, steering angle calibration, etc...

[RBB]

So, W///, the car is running just fine with the new actuator? I've always read and was also told by the dealer that the new actuator had to be initialized with their software or Autologic. Is this not the case?

[W///]

Originally Posted by RBB

So, W///, the car is running just fine with the new actuator? I've always read and was also told by the dealer that the new actuator had to be initialized with their software or Autologic. Is this not the case?

I thought so too, that's what I read from M5 board. After putting the engine back together, I used the BT tool to clear all the codes.... hoped for the best... started the engine and presto, no limp mode

Maybe all you needed to do is to clear the SES code, I have no idea. Drove the car to work this morning, so far so good.

[W///]

Here's my write-up. Please let me know if it's not clear (it's my first attempt).
http://www.m3post.com/forums/showthr...4#post12551474

[tunawi7cheese]

thanks for posting. All my lights came on this AM too. I don't have a code reader so cannot say what it is exactly. Base on your write up, I think I'm in the same boat. Great DIY write up too.

[never dies]

Sorry to resurrect an old thread...I'm kind of in the same boat here but my problem seems to be a bit more complexed since everything mentioned here was tried and tested and then some. Here goes..

Here's my issue in details (E92 M3 US-Spec):

So my S65 engine has failed due to a bad/incomplete rebuild and all my cylinders were experiencing piston lashing. Given the cost of the repair vs swapping the motor out, I went ahead with a 2nd hand motor (22,000km) from a RHD E90 M3. Engine swapped, tests and service done, car delivered back and I couldn't ask for more.

However, one month later the car started displaying at random a weird problem. Some mornings it would fire up immediately, and some other mornings I had to try a few times till it fired (would start and immediately bog down). Sometimes after a drive and parking the car for a few hours, it would do the same too (engine is NOT cold). Until the day came where it wouldn't fire up and keep idling at all. Car sent back to indy and diagnostics run. Turned out with these errors:

- 2B25 Throttle-valve monitoring; Bank 1
- 2B26 Throttle-valve monitoring; Bank 2
- Unidentified fault Code 2B57

The following has been done in the given order:

1) Replaced throttle sensors (both banks). No change.
2) Replaced throttle actuators (both banks) with 2 sets (from working E92 M3s). No change.

We have managed to start and keep the car idling, but it's always on limp mode (RPM 3K max). I have started the car and left it idling with the airbox disconnected from the engine (but connected it to the electrical socket and vacuum line) to monitor if the actuators levers are trying to activate the ITBs. NO MOVEMENT at all. The ITBs can be operated manually so they are not jam stuck.

So after we have confirmed the hardware part, we measured the actuators sockets power supply. Both measured 13.7V with the car idling. I have even connected one of the old, functional actuators (free, no load on it i.e. not connected to the ITBs) to the harness. Pre-drive check you could see the actuator lever moving a few tiny degrees (the click you hear from engine bay when you put the key in "ignition"). However, once the engine fired up, there was no movement from the actuator.

My questions is: Since power is obviously supplied to the actuators, what could the reason be for them not to function. Actuator socket is 9-pin, any idea which DME pins are the corresponding ones? Anybody who has faced this issue before?

Thank you and looking forward to hearing from you.

[CP Louie]

I understand the limp mode..

[panaderooo]

so did you fix this ? I got it today

[panaderooo]

I have a 2008 M3 coupe

[1MOREMOD]

Been covered. Cruise by local high school. Limp mode fixed.

[W///]

Originally Posted by panaderooo

so did you fix this ? I got it today

Mine ended up being the throttle actuator. But the only way to know is if you got the codes read.

Originally Posted by 1MOREMOD

Been covered. Cruise by local high school. Limp mode fixed.

Super helpful, thanks.

[1MOREMOD]

so serious! carry on.

[MikeD]

Hey guys, I got the p1268 code too. Is there a part number for the torx screws that bolts the TA housing down? I'm paranoid I will loose a screw as I plan on DIY