6.4 High Boost / Low Power Issue
I have a 2008 F-550 That we just installed a new engine. We installed a DPF delete package, EGR block off and SCT Live Wire tuner at the time of engine replacement. When you start up the road at 1/2 throttle, it will make up to 59 psi of boost (regardless of tune). It seems that once the truck gets to 55 mph the boost drops and the truck runs OK. At that point, full throttle we are getting about 41 psi of boost. If you stop and cycle the ignition key, it will go back to high boost. Only item I noticed is the EGR block off plate is installed on the top exhaust flange. I think it should be installed at the cooler on the left side (drivers) of the engine. We have blew (3) CAC hoses.