4 Attachment(s)
HELP: Turbo 5.3L LS1B lean at higher boost levels - can't adjust??
I've been beating my head on a wall for a bit here. Need some assistance...
The setup: 5.3L, FAST 88lb injectors, MagnaFuel pump, stock rails/regulator, 76mm single turbo, ~10PSI wastegate, COS5, 2bar MAP, SD tune, MAF disabled, Closed Loop disabled
The Issue: Engine runs solid up until about 150kpa, then no matter how high I adjust [A0009] boost VE table, I can't compensate with enough fuel to keep it near target...it consistently drifts leaner and leaner before I let off. Right around 150kpa, commanded injector pulse width starts to DECREASE as does CALC.CYLAIR value. I would have anticipated continued INCREASE of injector pulse width to match increasing RPM and boost level. Logging GM.DYNCYLAIR_DMA appears to match my 500% VE test configuration described below, however I cannot seem to get the system to command more injector pulse width to richen the mixture. I'm stumped!
Things I've tried:
* I checked both COS3 and COS5...same issue. Shot in the dark kind of test.
* Hooked up a fuel pressure tester. Helper verified correct rising rate pressure with boost.
* Set whole area in [A0009] map to max 500%. Same lean condition. No amount of movement in the boost VE appears to cause increased injector pulse width. (corresponds to "graph1.png" and "log 58.efi" attachments)
Tune and log files attached. Please help! :(
