[colman]

I have been working with a very reputable tuner on a custom tune (FBO, inlets, VTT OE turbos) for my manual 535xi wagon. It seems that once the initial boost target is around 16 or higher on the revisions, I overboost initially causing a throttle closure.

My tuner has noted that he removed all of the duty cycle, adjusted PID, air adder and this issue still prevails.

On my side, I replaced all vacuum lines and boost solenoids. Traction control is completely disabled on all logs. Here is the progression:

rev 2 (really clean)
https://datazap.me/u/criemersma1/rev...=0&data=3-6-16

rev 3 (adding some boost, throttle closure)
https://datazap.me/u/criemersma1/rev...data=3-6-16-19

rev 3 again (worse closure)
https://datazap.me/u/criemersma1/rev...=0&data=3-6-18

My question is what else could be the cause of this? Overtightened wastegates, 1M throttle sensitivity, adaptations?

[Sgop335]

Those TCs are not bad at all. Overall looks like a pretty good tune. Wgdc base can be reduced in the appropriate points to eliminate tc.

[Saif2018]

Originally Posted by colman

I have been working with a very reputable tuner on a custom tune (FBO, inlets, VTT OE turbos) for my manual 535xi wagon. It seems that once the initial boost target is around 16 or higher on the revisions, I overboost initially causing a throttle closure.

My tuner has noted that he removed all of the duty cycle, adjusted PID, air adder and this issue still prevails.

On my side, I replaced all vacuum lines and boost solenoids. Traction control is completely disabled on all logs. Here is the progression:

rev 2 (really clean)
https://datazap.me/u/criemersma1/rev...=0&data=3-6-16

rev 3 (adding some boost, throttle closure)
https://datazap.me/u/criemersma1/rev...data=3-6-16-19

rev 3 again (worse closure)
https://datazap.me/u/criemersma1/rev...=0&data=3-6-18

My question is what else could be the cause of this? Overtightened wastegates, 1M throttle sensitivity, adaptations?

Those are minor throttle closures, have you logged straight after flashing the map or done a couple of logs on the latest map (rev 3) for adaptations to set in first?

[Cloverdale]

If the boost solenoids are not new Pierburgs I wouldn't trust them. Attach a hand vacuum pump on the inlet stack and take to 30 lbs while holding your finger over outlet stack. If they don't bleed off (lose pressure) while doing this they're malfunctioning. The knock-offs don't bleed off even when not holding finger over outlet stack. This is not the only boost solenoid test but the one to start with.

[colman]

Originally Posted by Saif2018

Those are minor throttle closures, have you logged straight after flashing the map or done a couple of logs on the latest map (rev 3) for adaptations to set in first?

These were straight after flashing for the most part. I wasn't aware that adaptations could affect/smooth out the small overboost, but that does make sense. Thanks!

[Saif2018]

Originally Posted by colman

These were straight after flashing for the most part. I wasn't aware that adaptations could affect/smooth out the small overboost, but that does make sense. Thanks!

No worries.