So I'll try to condense this as much as possible for simplicity's sake, but the story is this: I bought a 2020 Mustang GT last year. Added a simple catback exhaust, then added LT Headers/cat delete, then decided I wanted to get serious & put a blower on the car. So I bought a VMP Odin kit. The installation shop is one that my brother works at and he performed the majority, if not all, of the mechanical work on the car. He's been working on cars and performance vehicles for over the past 10 years. Well after the install was done, they took it to their tuner to have it dyno tuned. The guy managed to get 720whp out of it. When I finally got to pick the car back up, I left the shop and got about 10 minutes away before the car started acting completely f*ed. Idle was sitting high at like 2k rpm, if not just bouncing up and down aggressively (kinda sounded like a cam, def not supposed to do that). AFR was also bouncing around like crazy. After this happened, almost right away the car went into "limp mode" (wrench light, powertrain fault warning, CEL, etc.) and I limped it home. Got it back to the tuner and then it seemed to drive fine for awhile. But the IATs were always high and we realized that the add-a-fuse that came with the VMP kit was bad. Also around this time, the car had started to perform really weird (idle surging when at stop lights and stuff, seemingly "losing boost" mid-powerband, and anytime I tried to put the car into reverse and use the clutch to back up like a normal person, the car just would not move). To put that into context, when the car was stock/pre-supercharger & tune, I could let out the clutch just a bit and the car would back up with plenty of power to go up inclines/over bumps. Now, to go up an incline or over a bump in reverse, I have to rev the car to 2k+. We went ahead and replaced the oil pump gear and the stock clutch mostly as a precaution but also to rule out a slipping clutch. When I got the car back, it felt better initially, but the "dying at stoplights" issue remained. After a few days, it's once again feeling like it has zero power in reverse without revving really high. And it dies in low speed/low rpm scenarios frequently. Slowing down when coming to a stop, idling, reversing, etc. are all potential catalysts to the engine dying. & I don't mean that the engine stalls. It just completely *stops*. Lights & everything still on when this happens as if I just turned the ignition off. Now the plan was to datalog the car and get the tuner to revise the tune, but I can't really drive the car much with the clutch still in the break in period (no WOTs, launches, supposed to stay outta the high rpm range apparently, etc) so I've just been logging some city driving here and there and I don't know what the hell is going on with the car but something is seriously wrong based off these logs. LT/ST FTs are good at some points, but then at others they're significantly bad, e.g. -25%+. All gaskets and vacuum lines were checked for vacuum leaks when my brother installed the clutch/oil pump gear, so I doubt it's that. Can someone take a look at the logs and give any kind of input? I know the data is limited but for some reason I can only record a handful of parameters because that's all that VCM Scanner shows available for my car...
Just a shot in the dark, but maybe the bypass valve is giving issues you need to test it with something like a mityvac that will apply vaccum and pressure . Also with scanner connected to the car you need to repopulate the list of channels
OP, did you resolve this issue? This is the exact same issue I am having and I am at my wit's end. Please update this post with any new one for you have, or let us know if you even were able to fix it. I'm about to throw in the towel on mine and this is my last ditch effort to figure out what the hell's going on.
Sounds like this thing has a laundry list full of different issues. Could be the MAF. Widebands. The Tune itself. If it had no issues before you added the vmp then I'd point the finger at the tune. As for the clutch and not moving in reverse. Very strange. Could be mechanical. Sounds like the tune needs work though if it's dying at stop lights. Limp mode could be caused from a TQ limit, maybe something was overlooked when the tuner was tuning it. Someone with more experience can probably help further into detail
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