GreenToxon

Hey everyone, just wanted to see if anyone had any ideas(I checked and there have been maybe 2 posts of something similar on the forums)

So I've got a 2016 5.0 with about 31500 miles on it. I had other issues before with my navigation crapping out, moonroof leaking whenever it rained, a paint bubble on the hood. But never really anything that was engine/drivetrain related.

Truck is completely stock with Mobil 1 Synthetic oil changes every 5k.

At about 30000 miles I noticed that when the truck was warm and it was idling that occasionally it would dip below the 500-600 rpm idle to around 250-450 and the truck would shake pretty bad as if it wanted to stall out. Drove it another week with the dip in RPM starting to become more frequent until a few days ago I was sitting in my driveway and the truck dipped and stalled. Then I was driving up the road with a steep grade for about 1/2 mile and came to the top, the light was red and in the middle of the road truck stalled again when I came to a stop.

Took it to the dealer and was able to recreate the problem so they could take a look at it. Doesn't have a CEL or anything but they had it the whole day and were able to make note of the problem but said it had a "base engine issue" and they needed their head tech to look at it this Monday.

Anyone have similar issues or heard about anything of the sort?

Drove a 2013 5.0 Mustang for about 40k miles before I traded it in for this truck and never had any issues. It was the same 5.0 (just slightly different on the F150's) but that had a tune/intake/headers etc and the 5.0 engine tick but it was perfect.

slamm

I have the same issue with my 15 5.0 SCrew. I have had it at the dealer 3 times with no luck.

Just last Thursday it attempted to stall and felt like I was going to loose the transmission. It threw a service hill decent warning and them smoothed back out.

GreenToxon

So quick update, truck was at the dealer on Monday and they got the code P0012 and decided that reflashing the engine was the best option. Said it was good to go and I picked it up that afternoon.

Wednesday morning now the rough idle has returned and it's a little worse when it happens. Came back after about 60 miles driven. Seems like it's a deeper issue and not just the "computer" as they described.

slamm

SO i put my truck back at the dealer yesterday and they think they have found the problem. Apparently there is a purge valve in the fuel intake system that is not functioning properly. They are replacing it and we will see what happens.

Regarding the Hill decent issue they are attributing it to a bad battery that was causing communication issues.

slowpony46

My 17 had those exact symptoms with 300 miles on it. But my check engine light was on. It wound up being a bad VCT solenoid.

svenny

My boss's 2016 lariat had same problem. It had something to do with the throttle body. I believe it's the throttle body spacer.
Mention it to the dealer.

joshuncc

I have the same exact issue. It showed up a month or so ago, and it is so random that I have trouble recreating it for people to witness. I have no check engine light on, so most people say they can't pull codes. I have noticed that it appears more frequent if I have been driving on the highway for a period of time (typically with cruise control), and then show to a stop (like at an exit ramp). Sometimes the rpm dive is enough to shut the vehicle off. I typically keep my foot on the gas and brake now at stops to keep the truck from turning off.

Has your issue been resolved yet? Any idea what is the culprit?

GreenToxon

Hey everyone, I totally forgot to update here.

So after having the truck at the dealer after they had "fixed" the issue after about 150 miles they said nothing was coming up and they couldn't recreate.
But I noticed that it would do it slightly differently now and it's gotten progressively worse again. I'm at 33295 miles and I just changed the oil at 32500 (every 7500 with Mobil 1 5W-30 Full Synthetic).

It's gotten really bad the last 3 days to where it shakes and rough idles just sitting in a parking lot after it has gotten up to operating temperature.

Today it stalled on me while waiting for a left turn arrow in the morning. And this afternoon after work merging onto the freeway it threw the CEL. The first visible CEL wtith this issue. I have a cheap scanner on him and I'll see what code it gives me.

I'll be taking it back to the dealer this Monday to see what they say.
Any recommendations on what I can do to contact Ford? The dealers don't seem to be able to figure it out.

GreenToxon

This has been exactly how mine started. If you go 80-90 on the highway and come to a sudden stop I bet it'll stall/idle badly for sure. I'll keep you updated!

joshuncc

I had just returned from a 2 hour trip from Charlotte, and when I pulled into the driveway and put the truck in Park I could hear it was stuttering. I turned on my phone and captured this.


I am driving to the mountains today and this makes me not want to drive my favorite vehicle (that only has 40k miles on it now).