Misfire Cyl 4 (2018 GT)

MaxHedrm

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It took me a whole 70 miles to break it. :frusty:

I picked up the car on Thursday with 5 miles on it. Drove it to work Friday and back home that night. Alas, no top down on the way home.
20180406-Rain-IMG_7114-1440.jpg


Friday night I updated Sync 3, was playing with all the dash lighting and other settings. when I started out back up after tweaking all the things, it was running like a tractor. & not a nice one. Lots of misfiring & a CEL.

It was 8pm, so the service department was closed. I had an amusing text conversation with my first sales guy who is now a service writer and he ended up calling the sales manager and arranging a loaner for me the next day. So, I got up Saturday & put Ford's roadside to work & joined the flatbed club.
20180407-Flatbed-IMG_7117-1920.jpg


I don't think they looked at it Saturday, but this morning I think they reset the codes about 6 times. I was barraged by half a dozen FordPass notifications.

The service writer finally called around 2 this afternoon. Misfires on cylinder 4. The "drivability" guy had checked all the obvious things like plugs & coil packs to no avail. He said they were handing it off to the next level of tech (I can't remember what he called him).

Wish me luck!

 

10r80

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Wow... I'm in Dallas as well, where did you buy it?
 

Cardude99

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That sucks. Hope they sort it out soon. I had a similar experience. Day I got my hellcat, within 50 miles threw a code, and went in limp mode. Luckily it was just a loose vacuum connection and I've had 6k trouble free miles ever since. I hope it's nothing serious. A broken new car sucks but warrenties exist for a reason
 
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MaxHedrm

MaxHedrm

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Wow... I'm in Dallas as well, where did you buy it?
North Central.

That sucks. Hope they sort it out soon. I had a similar experience. Day I got my hellcat, within 50 miles threw a code, and went in limp mode. Luckily it was just a loose vacuum connection and I've had 6k trouble free miles ever since. I hope it's nothing serious. A broken new car sucks but warrenties exist for a reason
Yeah, my only worry is that they'll have to tear into it to figure it out. :-/
 

wanted33

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Hoping it's something simple Max. I know seeing your new baby being loaded onto a flat bed made you sick. Good luck.
 


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MaxHedrm

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Heheh. They are working on it again. FordPass just blew up my phone. Some of them are amusing, some scary:
  • Malfunction Indicator Lamp - Regulatory (the usual CEL/MIL)
  • Forward Collision Warning - system fault or obstructed radar sensor
  • Powertrain Malfunction/Reduced Power - All-Wheel or Four-Wheel drive system has detected a fault (say what?)
  • Hill Start Assist Warning - Hill Start Assist system detected a failure
  • Malfunction Indicator Lamp - Regulatory (7 more of these)

They also drained the fuel tank, I'm not sure if they drained it completely & refilled it or just partially.
 
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hcappie

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When my ‘15 GT was still new it kind of out of nowhere ran rough and went into limp mode. I think it’s some random gremlin or the computer learning itself because it quickly composed itself and never happened again. I didn’t need to take it in to get looked at.
 
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MaxHedrm

MaxHedrm

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Mine went into "I'm shutting off now" mode. It wouldn't idle for more than a minute. Even when I tried to move it if I let off the gas idle would drop to ~300 unless I revved it a bit.
 

sijoko

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Did it have 87 octane in the tank?

Mine had a misfire on cyl 8 with about 120 miles on it. Still on the original fuel fillup from the dealership.

I cleared it after refilling with 93 octane and now have about 300 miles on the car.

But your car shutting off sounds like it's more than just an octane issue.
 

ANGST

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Hey but at least it doesn't vibrate at 50-70MPH ....


or does it ?
 
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MaxHedrm

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Did it have 87 octane in the tank?

Mine had a misfire on cyl 8 with about 120 miles on it. Still on the original fuel fillup from the dealership.

I cleared it after refilling with 93 octane and now have about 300 miles on the car.

But your car shutting off sounds like it's more than just an octane issue.
Yeah, more than gas for sure. Though they did empty the tank & put about a quarter of a tank back in it, just to be sure. It was probably the same dealer gas they put in it the first time though, so :shrug:
 
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MaxHedrm

MaxHedrm

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Hey but at least it doesn't vibrate at 50-70MPH ....

or does it ?
Hah. Only had it at highway speeds 3-4 times. But not that I recall.
 
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MaxHedrm

MaxHedrm

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Today's update:
Initial diagnoses - misfiring on cylinder 4, but also occasional misfires on all the others.

Their actions so far:
  1. Replaced the fuel
  2. Replaced the plugs - they were fouled after 70 miles somehow

Next steps:
  • Pull the head for further inspection
:frusty:
 

PoppinJ

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Today's update:
Initial diagnoses - misfiring on cylinder 4, but also occasional misfires on all the others.

Their actions so far:
  1. Replaced the fuel
  2. Replaced the plugs - they were fouled after 70 miles somehow

Next steps:
  • Pull the head for further inspection
:frusty:
Pulling the heads huh. That sucks man. Surprised they didnt try a bore scope first or something. Try and go talk to the actual mechanic performing all the labor. You might have to go up there but you would get a lot more info than whats being passed by the service rep. Good Luck. The 2018 Coyote is so new that Ford has a ton of parts on back order so hopefully whatever parts you need doesn't get slowed down by that.
 

 
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