How about this....

[HPEBrian]

Running an LS9 off an E38 ECM.... Sounds easy right? Definitely not. Won't even go into to boost for some reason wiithout shutting down. Took the actuator off and hooked the bypass up like a normal roots blower. Tried using the stock map sensor and scaling. Tried the 3 bar that comes with the LS9 with no luck. Tried SD, MAF only and normal and it all does the same thing. Once it sees boost cuts off. Don't get it I've tuned 900 magnuson and other various forced induction GMs of all various shapes and sizes and never had this problem. Hit's 86lb/min FAST.

Having trouble indentifying the problem. Any help or suggestions are welcomed.

Its like once you won't into boost dam fuel shuts off.


I've even made a pull holding the bypass valve open and runs fine. Doesn't compute.