Boost surging at 2500-4000 rpm

[Donny]

Hi guys,

I’ve been having boost surging issues on full and partial throttle during 2500-4000 RPM.
I’ve had this issue for a full year and could not resolve it. I have changed the full list
- index 12 injectors
- charge pipe
- intercooler
- hpfp
- walbro 450 lpfp
- vac lines to and from the turbos
- boost solenoids
- coils & spark plugs
- O2 sensors upstream

All have been changed but did not resolve the problem. I have also tried tuning with 3 different tuners but still end up with the same problem (MHD ots maps also have the same effect).

I’ve spent countless hours researching and found an answer leading to resetting the adaptation. I did the adaptation reset through MHD but still didn’t work. Can someone please help! This is getting very frustrating.
Thanks in advance.

 

[Donny]

datazap.me | PipeWerks | Boost surge

datazap.me

 

[rev210]

What turbos ?
Reducing wgdc through the surge zone is one strategy that would usually help. Assume tuners did this at some point?

 

[SlowE93]

I hate datazap but took a quick peek. The actual target looks weird to me.
Maybe its just the way my phone displays datazap which is why I hate lookn at logs on datazap.

 

[Jern54]

What is your BOV set up? You might check that to start with.

 

[Maroon_e90]

I'd wanna see your PID factors if you could. Its clear that the PID is freaking out at lower RPM to increase boost.

 

[turbohugh]

I wonder why the load req is so high, although I don't think that is the problem.
I think you have a mechanical issue. Have you tested the actuators? They both should be set to close ~7inches of mercury and not leak. Looks to my eye that you're having boost control issues with the WGDC fluctuations . I would vacuum test the actuators and confirm they are closing at the correct vacuum. You will have to remove the downpipes to be sure but a dirty test would be to make sure the arms are moving when you apply vacuum to the actuators and fully closed at the right vacuum , and aren't losing vacuum [a leaking vacuum diaphram in an actuator can do that]. It's something like that [in my opinion] that you will find . You may also have a 'sticky' actuator [this is related to the wastegate rattle issue]. IF you've solved this by now can you let us know what it was ?
All the best..

 

[carabuser]

Just looks like a tune problem in that log, you've got to do some pretty retarded things to the tables to get a boost target to look like that, no hardware fault would cause it.

Do you have a log of the problem with the MHD OTS maps?