VOLVO VNL 670 cummins isx 15 500HP

Hi to everyone.
It’s been few days maybe a week my truck is leaking air from somewhere, but i can’t find it. So this is what is going on.
As i accelerate i hear the air leak is louder. 5 seconds before the air dryer makes that sound “pshh” i guess its called before it purges the air leak is gone and if i accelerate there is no leak and now right after that pshhh the leak is coming back.

what can be ? could be Air dryer, governor, compressor ?

please help it drives me crazy. boost is good on the gauge

 

Well i can’t really tell. The only times it doesn’t leak air is 4-5 seconds before dryer purges. I would say the whole time.

 

i tried that. there is definetly some leak coming from the engine area when i hit the brake pedal.

 

but how break air leak can leak under boost ? i checked all the hoses cac no leak anywhere. i think is something with the dryer idk. i’m coming to the point where i have to replace air drywe annualy.