[DriM3]

So ive had my 335i for about 8 months now, second owner and have had shitty-ish luck with the car since purchase date. Recently its as if the power just packed up and moved away. WOT feels like a slug, doesnt randomly come back, doesnt surge; nothing. Half engine light came on for the short 10 minute drive out to lunch and disappeared an hour later when turning the car on again, and havent seen it since. Car will still start up fine and drive, but it feels like the turbos are just non existent. Scanned it on 3 different ODBII scanners and its showing no codes present or stored. Car does sound a little more raspier since the SES came on and has a slight more vibration at idle and has remained that way since.

Had the HPFP and injectors replaced about 6 months ago and did the waterpump 2 months ago as well. Full service a month ago (spark plugs, oil, power steering, brakes, etc etc). Read about the misfires/spark plugs/carbon build up possibilities but the car doesnt shake what so ever at WOT. Very confused and not sure where to look for a fix?! Any help where to look would be greatly appreciated!

[Lulz_M3]

Probably a wastegate that is sticking, or a boost leak. I'm assuming you are not running a tune? Find a local BMW specialist that can scan the codes, whatever caused your SES light in the past is in the history. Most generic OBDII scanners suck at reading BMW's. You could also look in the regional forums and ask for a member with a BT Scan tool or Cobb AP to be kind enough to read your codes.

[scflaw]

sounds like a severe version of what I have, which is a defective wastegate. (or least it seems like it). does it only happen at optimal tempurtures too?

[DriM3]

Just took the car out for a little spin and noticed an odd whine after having revved the motor standing still which ive read is characteristic or a wastegate issue. Also popped open the top airbox cover and gave it a few revs, didnt hear any sign of spooling unlike the last time I did this when I clearly heard the turbos spool....

And Car is completely stock, jb4 sitting in trunk waiting to go in....

[themyst]

Dealer it!

[DriM3]

Way out of warranty..

[ar design II]

is the exhaust any louder than it was before? no power and no spooling sounds like wastegate issues to me... Putting in the jb4 so you can log some data may not be a bad idea...

[scflaw]

Originally Posted by Kai @ AR Design

is the exhaust any louder than it was before? no power and no spooling sounds like wastegate issues to me... Putting in the jb4 so you can log some data may not be a bad idea...

haha i have that, i kinda like how the engine sounds angrier when the half CEL is on

[DriM3]

Yes louder and get a lot more of the back pressure pop/burble when stepping off the accelerator....wouldn't mind the louder exhaust if it had the power to match!

[ar design II]

Originally Posted by DriM3

Yes louder and get a lot more of the back pressure pop/burble when stepping off the accelerator....wouldn't mind the louder exhaust if it had the power to match!

Put in the JB4 with just map 0 then log it an see how much boost its making, if any.

Sounds like the wastegate/s may be stuck open.

[jdhart]

Originally Posted by Kai @ AR Design

Put in the JB4 with just map 0 then log it an see how much boost its making, if any.

Sounds like the wastegate/s may be stuck open.

+1, also put boost to fuel gauge so you can watch it in real time.

[DriM3]

Will have to give this a shot on saturday morning and get back to everyone on results....also is it not a smart idea to drive the car around if this be the case, that the wastgate is stuck open? I've been driving around the winter beater since the day the car started acting up since I obviously didn't want to do worse damage...