eigenvector

So I have had this over boost problem with my stage 2+ for a while now.. the chip is GIAC X..
I have been getting these codes...
17544 - Fuel Trim: Bank 1 (Add): System too Lean
P1136 - 35-10 - - - Intermittent

17884 - EVAP Leak Detection Pump: Insufficient Vacuum
P1476 - 35-00 - -

I have pressure tested the wastegate line and the intake.. I checked the fairly new 710Ns ..Didn't find a leak. I found that the small check valve that connects to the N249 valve was broken.. So I replaced it and it did not help.

I then proceeded to bypass the N249 to see if that was the problem and nothing changed.. I thought it could be my N75 so I replaced it and still nothing changed..

I checked to see if my exhaust was hitting that EVAP line and it was.. but I moved the exhaust a little and there is no hole or anything on that line to cause the EVAP code

When I put an MBC in place of the N75. Then it does not over boost..When the N75 is in, The actual boost goes past the spec boost then drops down then goes past it again.

There is also some weird part throttle hesitation..

My LTFT's don't look lean (see pic below)

<img src="http://pictureposter.audiworld.com/103335/ltft.jpg">


I'm stumped.. the boost will go over 20 psi on pump mode. In stock mode it goes to about 10.5 psi..

Wrinkledpants

Do the codes come back when you're running the MBC?

eigenvector

yeah I still get the codes with the MBC

5lugnuts

Pressure test w/ soap n water? Accordion hose tight to Maf &amp; Y pipe? O ring for maf intact?

eigenvector

I've done that already... yes tight.. yeah O ring intact

Wrinkledpants

from the uber knowledgeable people here.