M57 low to no power in 1st & 2nd gear

[N54TT]

Hey guys,

Just looking for some feedback.

My 335d is suffering some power loss. It's been deleted. I think this issue has always been there even with the system not deleted, but wasn't as severe. When I go WOT in first and second gear it feels like it has no boost then suddenly boost comes on in 3rd gear, but even if I randomly go WOT it will down shift to a lower gear and have no boost then all of the sudden gain boost in the next gear which happens to be 3rd gear and forward. The car doesn't even burn rubber off the line. Can this potential be because I haven't flashed with xhp yet to up the transmission torque limits?

All the pressure converter sensors and vacuum lines have been replaced. Even after testing I found them in working condition, but I replaced everything to play it safe. I can't think of any other vacuum line or sensor that needs to be replaced.

No stored fault codes or anything.

 

[wireboy]

Hey guys,

Just looking for some feedback.

My 335d is suffering some power loss. It's been deleted. I think this issue has always been there even with the system not deleted, but wasn't as severe. When I go WOT in first and second gear it feels like it has no boost then suddenly boost comes on in 3rd gear, but even if I randomly go WOT it will down shift to a lower gear and have no boost then all of the sudden gain boost in the next gear which happens to be 3rd gear and forward. The car doesn't even burn rubber off the line. Can this potential be because I haven't flashed with xhp yet to up the transmission torque limits?

All the pressure converter sensors and vacuum lines have been replaced. Even after testing I found them in working condition, but I replaced everything to play it safe. I can't think of any other vacuum line or sensor that needs to be replaced.

No stored fault codes or anything.

It sounds like the high pressure stage turbocharger isn't spooling up. I would take a look at the compressor bypass, turbine control valves and wastegate to see if they are working correctly. I have seen the compressor bypass valves and wastegate arms seize on higher mileage vehicles. I would perform the charge pressure test plan if you have access to ISTA and verify the operation of the wastegate, turbine control valve and compressor bypass valve. Test the movement of all three with a vacuum pump if you don't have access to ISTA.

 

[N54TT]

It sounds like the high pressure stage turbocharger isn't spooling up. I would take a look at the compressor bypass, turbine control valves and wastegate to see if they are working correctly. I have seen the compressor bypass valves and wastegate arms seize on higher mileage vehicles. I would perform the charge pressure test plan if you have access to ISTA and verify the operation of the wastegate, turbine control valve and compressor bypass valve. Test the movement of all three with a vacuum pump if you don't have access to ISTA.

Thanks for the response. A friend of mine has ISTA I will run that test and report back. My gut tells me the high pressure turbo might need to be replaced.