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Join Date: Aug 2012
Location: Carson City, NV Proud Participant, Federal Witness Protection Program
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So to be clear, engine idles well, has good balance rates but maxed out rail pressure and cuts out off-idle.
FPR was a good guess on the rail pressure issue, but throwing in oil dilution is a head scratcher, and those would seem to be unrelated problems.
“Having a issuse I can’t wrap my head around with my LB7”
As you know, electrical connections on old machinery can be a source of trouble and I’d suggest you disconnect and inspect connectors to the Fuel Injection Control Module (FICM) and anything else on the engine that may be accessible.
How long were you able to drive your truck with the high rail pressure MIL? Did that problem start after the fuel in oil situation?
Does your friend with the shop have a TECH2 (or similar) that would allow him to command a different rail pressure? That might at least show the CP3 is “following orders”.
Any other clues to share?
2003 GMC Sierra 2500HD SLE ExtCab CA Emissions; 155k; Allison 1000 w/Transynd X2 Flush & Fill; 8' bed; AFE/CAI; MBRP 4" Exhaust; Side Tint, 33% VLT, rear, Limo; Smittybilt Stainless Side Nerf Bars; Sprayed-in Bed Liner; MadJack Fuel Filter Access Door; Regular Used Oil Analysis (latest available on request), Blackstone Labs; EGT/Boost Gauges; Dual Chrome Dipsticks, JC Whitney; Stainless Steel fuel filter head bleeder screw; New WP and Hydroboost; Billet Aluminum Fuel Filter Housing Spacer; Professionally repaired instrument cluster (new steppers and lamps); Does anybody ever read this s%#t?; Injectors under warranty @ 70k; 2nd set DIY @ 155k