View Single Post
      11-15-2012, 11:32 AM   #15
Brigadier General
cssnms's Avatar

Drives: 2011 BMW 335d
Join Date: Sep 2010
Location: Murland

iTrader: (4)

Originally Posted by 335dwagon View Post
Went to the dealer today like I stated. BMW found nothing wrong. Now I will tell you this. I did have my Chipexpress tuner on Max setting when this happened. Before going to the dealer today I removed the tuner. They said they couldn't find a single issue with it. Any ideas on how to get rid of this factory setting in the BMW computer so I can run Max power setting on my tuner?
Thanks for the follow up. Glad to hear it wasn't related to the FMIC.

If the piggyback tune put your car into limp mode there should have been a stored code in the DME. Did the dealer try reading the codes? What does your paperwork say?

As for the piggyback triggering a limp mode, it's typical for such a devise when running at the max setting. By design they trick the DME into delivering more fuel to make the extra power - they do this by sending a signal to the DME that enough fuel is being delivered. The higher the setting on the piggyback the less fuel the DME thinks is being injected. Eventually (over time) the DME will determine there must be something wrong with the fuel pump in which ase it trigger a rail pressure sensor fault sending the car into limp mode. There isn't much you can do about it other than turn the piggyback settings down or go with a DME reflash.