Car will not stay running

[Zinc03svt]

My car was dying at idle with stock, 93 tune, and E85. Dealer replaced my intake cam phasers @ 6400 miles. FYI...

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[MaskedRacerX]

My car was dying at idle with stock, 93 tune, and E85. Dealer replaced my intake cam phasers @ 6400 miles. FYI...

Any other details you can share? Like when your car warmed up, was it fine? Other than that couple of days when it started then choked down/off, my specific problem is it starts, it idles down smoothly. Then in the first 15 or so minutes, if I do a stop, heavy gas, stop again (I'm talking going from 0mph to like 15 and back to 0), the idle just goes down, until it drops to 0 and the car is not running.

I experiences zero issues for the first month, this all started with the tune.

 

[Zinc03svt]

Any other details you can share? Like when your car warmed up, was it fine? Other than that couple of days when it started then choked down/off, my specific problem is it starts, it idles down smoothly. Then in the first 15 or so minutes, if I do a stop, heavy gas, stop again (I'm talking going from 0mph to like 15 and back to 0), the idle just goes down, until it drops to 0 and the car is not running.

I experiences zero issues for the first month, this all started with the tune.

Yes, generally after car warmed up coming to stop. Ford hooked up diagnostic tool and the intake cam phasers would slam to 0 degrees and car would go rough idle and die. Had been tuned since 175 miles. ;).

 

[Zinc03svt]

It started for me around 5800 miles.

 

[MaskedRacerX]

Yes, generally after car warmed up coming to stop. Ford hooked up diagnostic tool and the intake cam phasers would slam to 0 degrees and car would go rough idle and die. Had been tuned since 175 miles. ;).

Oh yeah, for me it's the opposite (if I'm understanding you correctly), i.e., once it's warmed up, it does _not_ do it.

 

[Diocletian]

Welp, put 5 gallons of good quality 93. Reflashed to flex and still it won't stay running. It turns over, stumbles and dies, even disconnected MAF. Should I try 93 tune even though there still like less the 2 gallons of E85?

 

[Zinc03svt]

Try stock tune.

 

[Mustang Tony]

I'd go back to stock and see what the dealership says. Damn, that sucks.

 

[Diocletian]

For whatever reason, I can't select my stock tune anymore from the ngauge menus, even though it's on there. I have a backup I think, but I was curious and tried to switch to the 93 tune and fired it up again. Same issue, wouldn't stay on.

This is becoming a damn nightmare, I have a $50k paperweight in my garage the past 5 weeks lol

 

[MaskedRacerX]

For whatever reason, I can't select my stock tune anymore from the ngauge menus, even though it's on there. I have a backup I think, but I was curious and tried to switch to the 93 tune and fired it up again. Same issue, wouldn't stay on.

This is becoming a damn nightmare, I have a $50k paperweight in my garage the past 5 weeks lol

Geez, that sounds like it's potentially a tuner issue if it's acting janky like that.

 

[MaskedRacerX]

Oh yeah, FWIW, my started as expected yesterday (really I only had those couple of days of starting issues), and it idled perfectly, even while pretty cold, and it ran great. I mean, I still have a CEL (assuming it's those same two codes), but in terms of operating behavior, it was solid.

 

[Diocletian]

So I unplugged the MAF and the car started and stayed on but 5 seconds after starting it idled like dogshit, but it didnt die! It certainly wasn't driveable though. So now what is it? If it was 100% the MAF then it should've idled a little bit better and be somewhat driveable right? A friend seems to think I might also have a vacuum leak past the MAF but me and 2 others looked over the engine bay and found nothing so we're stumped

 

[Diocletian]

Things left to try before I give up and surrender the car to Ford:

1. Switch to stock tune. Try again with MAF plugged in and then disconnected depending on results
2. I have a replacement OEM MAF coming in tomorrow I will try as well, because multiple signs are pointing to a bad MAF(wildly varying voltage readings, confirmed by Lund and myself, degradation in performance, car stays running when unplugged) and I already tried using sensor cleaner a while back when this started happening

Worst case is I have to find a way to purge the remaining 1.5 gallons of E85 out of the car and PRAY Ford doesn't find out, or I'm screwed. Hopefully, this has a happy ending because I'm about at my limit here and thinking I may have a massive engine issue.

 

[Zinc03svt]

Have you checked your battery? Does it run on stock tune?

 

[Diocletian]

Have you checked your battery? Does it run on stock tune?

It's a brand new battery I got last week, I even have a tester/charger so I know it's working fine.

I haven't switched to the stock tune yet, that's first on my list to try tomorrow

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