[TommyV9]

My e90 has a JB4 installed and I did an MHD BEF earlier this week. Per the instructions I updated the firmware for the JB4 prior to the flash. Unfortunately this later firmware eliminates the auto clearing of the codes for a catless downpipe.

I've done a bunch of reading and found a couple places where is was suggested to just code out the diagnostics in the .bin file using TunerPro. I went in and did this, but would like confirmation from someone that knows this stuff that this will work and won't screw anything up. I went into the .bin file and under Toggles>Diagnostic Codes>29F4 (Cat Conversion Bank 1) and 29F5 (Cat Conversion Bank 2) I changed the 56 to 00.

I'd put up a screen shot, but don't know how to do that, LOL!

[TommyV9]

Update: I knew I potentially had an issue as I tore the MAP sensor o ring when I tried to install it in my new aluminum charge pipe last week. The only o ring I could find locally was a little small. I had the first opportunity to really get on it Friday night and shortly thereafter went into limp mode. I had the new correct sized o ring in hand and replaced it Saturday morning.

Initially I had some issues, then realized I had not plugged the MAP sensor back in. I had to remove the charge pipe to change the o ring. Reinstalled it and cleared all the codes and now my SES light is off!

This started with:
29F4 catless downpipes detected
29F5 same
2C7B Lambda propel behind catalytic converter 2, signal
2DED Power management, standby current control

The 2 catless codes are still there but are not throwing an SES light. Not sure how this worked out, maybe it was all the o ring leaking boost that caused other issues. I’ll keep an eye on it.