Boost Issue After SCH Repair

[OMMMG]

Hi All,

I have a boost issue with my car and can't figure it out.

Mod list: BMS intakes, VRSF DPs, Chargepipes n J-pipe, no exhaust (open DP), New NGK 1 step colder plugs gapped to .018 n new coils. BM3 Stg AGG map.

Originally I spun the crank hub and had a BMW master tech take care of it on the side. He fixed it and re-timed the motor, added the Vargas Lock Bolt.

Got the car back and went from Limp mode making 0 boost to making very little boost. With no tune, on the in car power gauge, it won't go past 200hp n 240tq n that's like full redline. I'm getting walked by literally everything.

The car spools ok up to 4k rpm n struggles after that. I drove it a few days n realized it wasn't driving like before. My tech said drive it a few days and if no lights turn on, put the BM3 stg 2 back on.

I put the tune on n the it barely did anything, only shows running 4lbs of boost.

I've checked for boost leaks and there are none. I feel like it could be wastegates being stuck open, but everyone says its unlikely to fail cause they are electronic.

I previously got a error that said excessive airflow. I had another bmw master tech run codes with a bmw pro tool and it said that one of the after cat o2 sensors showed a short and a mass air sensor was not reading right.

so I cleaned the mass air sensor and swapped them from bank 1 to 2 to see if the the sensor is bad for the connector. I unplugged the o2 sensors to make the short go away to see if that helped.

The car got a little peppier but not by much. But it's no longer saying excess airflow, so I guess that's good.

So has anyone run into this issue or have any ideas that I haven't thought of? Would greatly appreciate any insight.

[blockdoc]

Originally Posted by OMMMG

Hi All,

I have a boost issue with my car and can't figure it out.

Mod list: BMS intakes, VRSF DPs, Chargepipes n J-pipe, no exhaust (open DP), New NGK 1 step colder plugs gapped to .018 n new coils. BM3 Stg AGG map.

Originally I spun the crank hub and had a BMW master tech take care of it on the side. He fixed it and re-timed the motor, added the Vargas Lock Bolt.

Got the car back and went from Limp mode making 0 boost to making very little boost. With no tune, on the in car power gauge, it won't go past 200hp n 240tq n that's like full redline. I'm getting walked by literally everything.

The car spools ok up to 4k rpm n struggles after that. I drove it a few days n realized it wasn't driving like before. My tech said drive it a few days and if no lights turn on, put the BM3 stg 2 back on.

I put the tune on n the it barely did anything, only shows running 4lbs of boost.

I've checked for boost leaks and there are none. I feel like it could be wastegates being stuck open, but everyone says its unlikely to fail cause they are electronic.

I previously got a error that said excessive airflow. I had another bmw master tech run codes with a bmw pro tool and it said that one of the after cat o2 sensors showed a short and a mass air sensor was not reading right.

so I cleaned the mass air sensor and swapped them from bank 1 to 2 to see if the the sensor is bad for the connector. I unplugged the o2 sensors to make the short go away to see if that helped.

The car got a little peppier but not by much. But it's no longer saying excess airflow, so I guess that's good.

So has anyone run into this issue or have any ideas that I haven't thought of? Would greatly appreciate any insight.

I would respectfully suggest that you have your Master Tech trouble shoot this. Is there a reason why you arent? Are the charge pipes attached?Too many variables and he did the work..othersise you are shooting in the dark

[Alan l.]

How does a “master tech” give back a car in this condition and expect driving it for a few days just correct itself?

Better take it to a legit shop to have it looked over. Too many things could be causing your issues...

[OMMMG]

Originally Posted by blockdoc

I would respectfully suggest that you have your Master Tech trouble shoot this. Is there a reason why you arent? Are the charge pipes attached?Too many variables and he did the work..othersise you are shooting in the dark

The problem is the tech did the crank hub repair and then got a job promotion out of state and had to leave. So I kinda got left high n dry. But yes all pipes are attached.

thanks for your help,

[OMMMG]

Originally Posted by Alan l.

How does a “master tech” give back a car in this condition and expect driving it for a few days just correct itself?

Better take it to a legit shop to have it looked over. Too many things could be causing your issues...

I guess that's what you get for a side job n spending half what BMW charges you.

Yeah seems I have no other choice at this point.

Thank you for your help,

[Luluu]

Sounds like you have a boost leak, this happened to me when my coupler popped off.

[Kev608]

Get a boost leak tester. They're fairly inexpensive and something you should be doing anyway.