[Maddox Parkin]

Hello I’ve been experiencing some weird stuff with my N54. It runs and drives good but at idle it will kind of kick a little bit. No misfires, no codes at all for anything. The kick isn’t bad but definitely noticeable, if isn’t constant it will happen once ever 5-10 ish seconds. I’m running a Jb4 mhd bef using the PUMP_USA and I don’t believe this issue is related because it does it even when I turn it back to stock tuning. I also have an issue with power delivery, not only is my power delivery pretty inconsistent it has no power below like 3.5k rpm’s and sometimes even higher, for example I’ll be going 35 in 3rd and I’ll step on it and really won’t go anywhere but if I was in second and did the same I would take off like a rocket. I’ve replaced my boost solenoids within the past 100 miles and recently did catless downpipes. This problem has existed since I got the car and I got it stock. I do have lots of wastegate rattle and do have problems building boost quickly, from what I’ve read full boost should be achieved at about 2.5k but I’m lucky if I get full boost at 4K. I do manage to hit full boost which is around 16-17 but it takes a few seconds. I’m thinking it could possibly be a vacuum leak so I’ll check for that. Also might be worth noting that my mpg is pretty low, about 18mpg but I never do highway driving.

[LucaN54]

check for vacuum leaks, maybe the lines to the brake booster? this was my prob.. and my full boost is around 2500rpm

[Maddox Parkin]

Originally Posted by LucaN54

check for vacuum leaks, maybe the lines to the brake booster? this was my prob.. and my full boost is around 2500rpm

Yeah one of the likes to my brake booster coming from the right was completely split in half but I already fixed it so there must be another leak somewhere

[OMEGA412]

Originally Posted by Maddox Parkin

Hello I’ve been experiencing some weird stuff with my N54. It runs and drives good but at idle it will kind of kick a little bit. No misfires, no codes at all for anything. The kick isn’t bad but definitely noticeable, if isn’t constant it will happen once ever 5-10 ish seconds. I’m running a Jb4 mhd bef using the PUMP_USA and I don’t believe this issue is related because it does it even when I turn it back to stock tuning. I also have an issue with power delivery, not only is my power delivery pretty inconsistent it has no power below like 3.5k rpm’s and sometimes even higher, for example I’ll be going 35 in 3rd and I’ll step on it and really won’t go anywhere but if I was in second and did the same I would take off like a rocket. I’ve replaced my boost solenoids within the past 100 miles and recently did catless downpipes. This problem has existed since I got the car and I got it stock. I do have lots of wastegate rattle and do have problems building boost quickly, from what I’ve read full boost should be achieved at about 2.5k but I’m lucky if I get full boost at 4K. I do manage to hit full boost which is around 16-17 but it takes a few seconds. I’m thinking it could possibly be a vacuum leak so I’ll check for that. Also might be worth noting that my mpg is pretty low, about 18mpg but I never do highway driving.

Post a log, but it sounds like your wastegates are toast.

[Maddox Parkin]

Originally Posted by OMEGA412

Post a log, but it sounds like your wastegates are toast.

https://datazap.me/u/maddox-parkin/l...log=0&data=1-4
Yeah it’s possible, I also forgot to mention that when I got the car one of the vacuum lines to the canister was completely unplugged and while it was unplugged I had absolutely no wastegate rattle but was very very low on power. As soon as I plugged it in I had really bad wastegate ratte even at idle but I am catless so the rattle sounds a lot worse. If it is wastegates am I just in the market for new turbos? Don’t really have the money for that with installation lol

[OMEGA412]

Originally Posted by Maddox Parkin

https://datazap.me/u/maddox-parkin/l...log=0&data=1-4
Yeah it’s possible, I also forgot to mention that when I got the car one of the vacuum lines to the canister was completely unplugged and while it was unplugged I had absolutely no wastegate rattle but was very very low on power. As soon as I plugged it in I had really bad wastegate ratte even at idle but I am catless so the rattle sounds a lot worse. If it is wastegates am I just in the market for new turbos? Don’t really have the money for that with installation lol

Just looked at the log, your afrs are a little higher than you would normally want to se. 12.8-15 on wot which is too lean. Also your waste gate duty cycles are pegged at 100. And boost is wayyyy below threshold but it rises steadily. If it was a boost leak it would more so hit a certain psi and stay there. So theres 3 things thar could be wrong, bad wastgates, bad vaccum pump, or vaccum leak. A bad vaccum pump and/or a vaccum leak should cause your brake pedal to be unnecessarily stiff. The wastegates are controlled by vaccum so if theres a leak in the vaccum system or a failing pump it could lead to the waste gates not shutting properly.

[OMEGA412]

Replacing turbos is a pain but doable yourself, theres plenty of tutorials. You could try rebuilding the wastegate or get ebay turbos

[Maddox Parkin]

Originally Posted by OMEGA412

Replacing turbos is a pain but doable yourself, theres plenty of tutorials. You could try rebuilding the wastegate or get ebay turbos

Yeah but I’m a 335xi so I have to deal with all the complications that the X Drive stuff adds to the installation and removal, I’m already interested in new turbos and may just go with some 17t or 19t turbos or maybe even ST

[Joe2ehusky300.]

Im having damn near the same problem from 2k rpm to 3k rpm it sounds like the car has a boost leak and builds Mabe 1-3 psi then as soon as Im past 3k rpm the car absolutely rips like there’s nothing wrong it seems like the first turbo isn’t working at all and I’ve done everything possible to fix this that I can think of you can physically hear it sounds like a bad leak WHOP- WHOP-WHOP from 2k to 3k then it’s fine.. I’ve replaced now 2 new oem boost solenoids, brand new burger charge pipe and tial BOV, smoke test passed with flying colors Multiple physical inspections of fmic, all hard piping, vacuume lines etc.
It’s not a tune issue everything there functions as it should. I’m JB4 with MHD back end flash with catless downpipes FBO and oem turbos. Had 30ff code and have been chasing it down for about 2 weeks now. I’ll post a log I did today any help would be really appreciated. Thanks.

[Maddox Parkin]

Originally Posted by Joe2ehusky300.

Im having damn near the same problem from 2k rpm to 3k rpm it sounds like the car has a boost leak and builds Mabe 1-3 psi then as soon as Im past 3k rpm the car absolutely rips like there’s nothing wrong it seems like the first turbo isn’t working at all and I’ve done everything possible to fix this that I can think of you can physically hear it sounds like a bad leak WHOP- WHOP-WHOP from 2k to 3k then it’s fine.. I’ve replaced now 2 new oem boost solenoids, brand new burger charge pipe and tial BOV, smoke test passed with flying colors Multiple physical inspections of fmic, all hard piping, vacuume lines etc.
It’s not a tune issue everything there functions as it should. I’m JB4 with MHD back end flash with catless downpipes FBO and oem turbos. Had 30ff code and have been chasing it down for about 2 weeks now. I’ll post a log I did today any help would be really appreciated. Thanks.

Do you have any wastegate rattle? If you’ve replaced all vacuum lines and boost solenoids then I have no clue what else could really cause it if you are getting full boost at higher rpm’s, the rump from like 4 psi to 15 in a span of 1k rpm’s is insane. I wouldn’t think it could be a boost leak due to you hitting your target psi but I can’t be to sure. That weird sound is interesting. Have you had it properly diagnosed? Would only cost you about $200 for a good shop to diagnose it and that could save you lots of money instead of replacing random parts.