Codes, no boost and no clue



Posted over on the N54 Tech site yesterday morning and I am waiting for some input and thought some experts here might point me in the right direction.

FMIC and stock intake. This happened after I tried again to mix 4 gallons of E85 with 93 octane using map 5.


2774 Mass airflow too high -- Ignore, tuner code
2C57 Reduced power mode / Boost disabled
2906 No Description Found
2C90 Blow-Off valve mechanics -- Ignore, tuner code

I can't find 2906 anywhere.

attaching current log and log when running E85 mix prior to faults.


Installed new JB4 back in March and ran on Map1 with 93 octane until September when I connected existing harness Flex Fuel wires and mixed in 4 gallons of E85. Had Injen intake back then which I have since removed. Car ran beautifully and all was good, log attached. After around two months, terrible misfire. Local well respected BMW shop diagnosed two faulty injectors. At my request also replaced all plugs and coils with OEM parts.

Have run for a month or so now on Map1 almost scared to try E85 again and I guess it was well founded as yesterday morning I mixed 4 gallons and no misfire but limp mode (half engine check engine light) and no or very little power.

I should add that when switching between maps the cluster froze and when it recovered around ten seconds later the trip odometer had reset which I thought was odd.

Not indicting the shop at all and sorry for the book but when diagnosing more information is always better in my experience.

I double checked the JB4 ground and power wires and all sensor connections.