[jayphil]

Hi guys,

I am looking for some help trouble shooting my problem. My car started to drive real bad and having drivetrain malfunction warning every time starting the car and while acceleration. I had a water pump code so my mechanics started by changing this. At first the car was not driving much better (max boos 3.5 psi) after the waterpump but 24 hours later the car was starting to show some boost but not holding it. Now I am not having the malfunction warning unless I do multiple pulls but I did log the car tonight and result is still not satisfying to say the least. I do not have any check engine light but the code that sometime appear is that boost pressure to low.

My car is a 535i xdrive 2011 120k KM (75k miles), only modification is JB4, K&N air intake, ER******** (but I put the catalytic converter back on because I was tired of the noise), axle back exhaust. Tonight pulls were done in MAP 5, 3 times in 3rd gear + one acceleration.

Target boost reach 16 psi but the car fail to deliver anywhere near that.

Any idea were the look for? We have tried to change the boost pressure converter with no success but not sure where else to check (Diverter valve, MAF, boost leak, bad turbo (there was not appearance of shaft play on the hot side )


Please look at my log and help me out!

[Dave @ BMS/Fuel-It!]

Looks like a major leak.

Have your pressure tested the system?

[jayphil]

Originally Posted by Dave @ BMS/Fuel-It!

Looks like a major leak.

Have your pressure tested the system?

Dave,

No I have not pressure tested the system yet. My Indy was not equipped for that.
Does a Smoke test good or better to find a shop that is equipped for a pressure test? Maybe I should call my dealer...

Thank for you help and I hope it is "just" a leak and not turbo related!

[Dave @ BMS/Fuel-It!]

Smoke test can usually find most leaks.

Sometimes a boost leak test is “better” some leaks don’t appear until higher psi etc

[jayphil]

Update (still having issues)

Hi guys,

I went to the dealer (in fully stock form) and they cleaned all sensor, changed the boost pressure valve and the diverter valve next to the turbo. After that the car was hitting boost hard but still got the drive train malfunction. I also have done a boost leak test and no leaks found.

Today I did some log and the car hit 22 psi even if the car request stock boost ~10psi (JB4 map 4), WGDC show 0... The issue is not JB4 related because it was removed from the car since last summer.

My car is back to stock except JB4 map 4 for logging only.

Logs are attached.


Codes are:
120208 Boost pressure control. Upper: boost pressure too high
120408 Reduced power mode
122108 BOV plausibility - Ignore, tuner code

Any idea where to look next. Issue with the Wastegate?

[Dave @ BMS/Fuel-It!]

Can you unzip the file please?

[blackhat75]

That log is confusing. Why is wgdc dead? Why is meth always 100? Looking forward to Daves review...

[jayphil]

Originally Posted by Dave @ BMS/Fuel-It!

Can you unzip the file please?

Sorry here it is unzipped!

[andrews013]

Originally Posted by jayphil

Sorry here it is unzipped!

This is scary. Really high boost, lean, hpfp very low. I think you have a wastegate issue, causing extreme overboosting. My question is why the JB4 didn't throw you into a safety map.

edit: oh wait, you're already in the safety map.

[jayphil]

Originally Posted by andrews013

This is scary. Really high boost, lean, hpfp very low. I think you have a wastegate issue, causing extreme overboosting. My question is why the JB4 didn't throw you into a safety map.

edit: oh wait, you're already in the safety map.

Yea I have tried map 1 but JB4 was doing its job to put me back right away in map 4. This run was done in map 4 all the time for logging only.

I hope if it is a wastegate issue that it can be resolved without a new turbo... I am actually planning to change this car by the end of the year...

[Dave @ BMS/Fuel-It!]

You need to address the hardware issue

[jayphil]

After a year of troubles all resolved now!

BMW Dealership give it a try to rechange the boost pressure converter under warranty (because they changed it in March), reset all sensor, position / adapdation etc.

The car is running perfectly in Map 0 and Map 1, boost constrol follow targets etc.

What a relief.

Thanks everyone that took time to respond to me in the post.

[Dave @ BMS/Fuel-It!]

Originally Posted by jayphil

After a year of troubles all resolved now!

BMW Dealership give it a try to rechange the boost pressure converter under warranty (because they changed it in March), reset all sensor, position / adapdation etc.

The car is running perfectly in Map 0 and Map 1, boost constrol follow targets etc.

What a relief.

Thanks everyone that took time to respond to me in the post.