[AndrewC1989]

Full bolt on jb4 n54 335i. AA BOV. jb4 is NOT g5 but has latest firmware. Map 2 14.5psi is what the car is always set at.

the car was misfiring also but i changed my plugs and one injector and that problem went away. the boost issue and the codes however did not. the codes are as follows:

p2096: Post catalyst fuel trim system too lean bank 1 Confirmed
p2270: Oxygen sensor signal stuck lean bank 1 sensor 2 confirmed[IMG]zz[/IMG]
p2098: post catalyst fuel trim system too lean bank 2 confirmed
p0174: bank 2 system too lean confirmed
p0174: bank 2 system too lean pending

(some codes are obv do to the catless pipes)

the boost drop issue remains. my thoughts are that either the BOV is leaking under load or that the temp sensor is shot and the jb4 thinks oil is above 260F and is not allowing the car to go above stock PSI for that reason. Car is going in for a diagnostic in a few days. any ideas or suggestions are appreciated.

Video showing and explaining the problem is below

*UPDATE* 9/5/14

went to a bmw dealer and explained the problem to my service advisor. heres the email i got back after dropping the car off for the day



Obv i declined a majority of the work. My advisor assured me a faulty 02 sensor wouldn't be the root of the issue and told me i could take the tech out with me for a test drive after the oil filter housing gasket was fixed and replaced today. I told him the car was not leaving the dealership until the problem was correctly diagnosed. This is annoying to say the least.

Has anyone had a similar issue? Can an oil leak be the cause for a drop in boost pressure?

car leaves bmw after fixing the oil leak

[AndrewC1989]

*Update 9/12*

car now shows misfires in cyl 4,5,6 and is extremely rough at idle. no limp mode. shakes like crazy when given throttle. feels like another bad HPFP to me but i can't be sure. back to bmw we go.


*Update 9/19*

car was taken from bmw after they suggested replacing all injectors plugs and coils for an additional $3000 and was brought to Helix Motor Sport in manayunk (Philly) where i happened to have purchased my intercooler a while back. Turns out it was ONE bad injector and a busted vacuum line inside of the intake manifold. So with injector 6 replaced and the G5 and 2STEP added, the car was running well. also turns out you aren't supposed to leave the DP fix in? that's why i was getting 02 codes left and right im assuming. I was also told my old jb4 unit was overboosting at like 20psi on map 1?! no wonder my BOV was so loud lol. Here's my fav DJ Unk Song for ya since i got me some 2step:

*Update 9/19*

On the drive home (map 5) i noticed the blow off valve is much quieter (Lower boost on new g5 board probably since the old one was targeting wayyyyy to high without my knowledge) and the same drop in boost issue persists from the very first video posted in this thread. i restarted the car and after another 60mph+ pull in 3rd gear went into limp mode. could it be the faulty oil sensor thats causing me to go from map 5 to 4 and lose boost and limp?! thats whats getting addressed next because i can't stand this car not working properly anymore