Need Help with 12' Coyote 5.0 VMP idle hang problem
Hello Gents
Im an engine builder / tuner down here in Brazil and I'm starting to tune newer ECMs , so far Im having good success with 4th gen GMs, but at this moment I have this 12' Mustang Coyote wich is fighting me hard. This ECM was a mess that other shop did.
Car have a stock auto trans/ converter/3.15 gears.
Engine is newly rebuilt 5.0,stock cams, forged internals, 11.25 CR pistons , VMP odin S/C at 12 psi ,VMP twin blade 69mm TB, long tube headers, DW 1000 cc injectors , 6" CAI, with new MAF sensor installed ,new 8# NGK plugs and new MSD coils.
So far the engine is working ok, actually runs with premium pump gas (97 octane), I've turned on the flex fuel logic to use ethanol mixes, mainly for power and safety due the high CR combined with this stout boost level.
I also installed a catch can connected to both valve covers, so the crankcase fumes aren't entering the intake manifold anymore.
The problem I'm fighting is: engine cold start is perfect, rpms go to 1300 and slow down nicelly to idle (880 rpm) , but as soon as I throtle it, engine revs nice but the rpm will hang at 15-1550 and slooowwwwwwlly dacays to idle.
The spark source goes to torque control instead of idle spark and I've tried everything I know and have read here to solve this problem with little to no success.
I've tried Torque tables, driver demand, MAF period, stoich ratios, CL/OL activation, TB area and angles, MP0 timing MBT and borderline, idle rpms....nothing solves the problem.
I also adjusted the minimum TB opening , its at .4? right now, so its not the culprit (was at 8? before)
I'll post the a LOG and file soon, I may be missing something...( I Hope)
Any help and tips will be greatelly apreciated, thanks in advance
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