Surging boost

[LIL DAVE]

Whats up fellas, here is the deal i had my 08 GMC dually tuned last week with EFI live, love the tune but here is the deal the boost surges(up & down) when i give the truck light to moderate throttle the boost is not steady. It's only steady at full throttle

Here is my question what tables need adjusting so i can let the guy know what needs to be done

Thanks Dave

[killerbee]

Good luck with that one. It has been a mystery from Hell. There are P.I.D. tables that should theoretically help with this, but nobody wants to play with it. It is going to be vane related. They are all over the place when this happens. There is some inherrent instability, in either the software, or the vane controller.

[bballer182]

Good luck with that one. It has been a mystery from Hell. There are P.I.D. tables that should theoretically help with this, but nobody wants to play with it. It is going to be vane related. They are all over the place when this happens. There is some inherrent instability, in either the software, or the vane controller.

Or the other obvious problem...

(undiscovered / unreleased) vane/boost tables.

[vortecfcar]

Typically, lowering the desired boost tables helps in my experience. The turbo has a greater tendency to surge with aggressive desired boost tables.

Nick