Shudder at Speed/Infotainment Dead

[SILK]

Hey gang!

First off, I'm new to post but I've been lurking for a few months. This forum is one of the best automotive forums that I've come across. Having Ford engineers actively in these threads is wonderful. I haven't had any issues until now, and now I have two fairly significant issues happen at once.

I have a (late) 2019 XLT with 7,500 miles. This weekend we were on a trip that requires about 3.5 hours of driving. About 2.5 hours into the drive, we approach a hill on the highway somewhere between 60 and 70mph. All of the sudden the truck begins shuddering terribly. I hit the brake to take the truck out of cruise control and the shutter goes away. I gently press on the gas and it returns. The check engine light comes on and flashes. I pull off at the next exit and shut the truck off. I wait a couple minutes then I start it back up. Light is gone. I begin driving and all seems normal. Then as I attempt to merge back onto the highway, the shudder returns. I'm able to modulate/prevent the shuddering by gentle application of the throttle. The check engine light does not return this time. I gingerly limp the rest of the way and make it the final hour. As soon as we got there, I checked the FordPass app and saw the check engine light malfunction there. The app said that an "engine misfire condition occurred" and could be caused by "poor fuel quality or a powertrain malfunction." I searched here and elsewhere for possible causes and find that it could indeed be bad gas, so I fill my tank up (it was at half) and hope for the best. Unfortunately, that did not fix the issue. The truck sat for a day and then it was time to head home. I found the nearest Ford dealer and stopped into Romeo Ford in Kingston, NY where they politely saw me immediately. The foreman scanned the truck, confirmed the misfire condition causing the light, but said that it had cleared and I was "good to go". I figured that the issue would not be fixed by this quick check and indeed it did not. But the dealer said that it was "ok to drive" and that I should get it into a dealer closer to home to do a deeper dive.

I found out on the drive home a few interesting tidbits:
- It does NOT occur from a stop, like the more common shudder that's been addressed by the TSB
- It only occurs above 3rd gear
- It seems to only occur in between 1,500 and 2,500 RPM when moderate pedal input is applied. Doesn't happen during light pedal input, or when coasting.
- This means that passing, going up hills, and merging onto the highway are a big problem
- There are no issues above 3,000RPM, I can accelerate just fine in any gear that I tried (4, 5, 6, 7)
- If it WAS bad gas, would I be able to accelerate like that? Wouldn't a misfire be even more pronounced if it were bad gas at that RPM?
- I can defeat the problem by manually shifting gears -- downshifting an extra gear to get above 2,500RPM before going up a hill

Another issue that popped up that's never happened before is that my infotainment system died about 3 hours into each drive. The screen goes black and the USB ports stop outputting power. The radio and all infotainment functions also cease. Turning the truck off and on only solves the issue for about 5 minutes before the screen goes dark again. After sitting for a longer period of time, the system works again. I updated to 3.4 (I forget which rev - but it was the bad one that removed climate controls for everyone and was eventually pulled off Ford's update website) in August and have never had the issue before, but I also have never driven 3 straight hours before without a significant stop. Anyone else have this?

Could these two large issues be linked? Does the PCM also interface with Sync, or is Sync a different computer system entirely? Could the PCM be the culprit here and a reflash would fix all issues? The trans shifts fine, and outside of the troublesome RPM's, the engine seems fine as well.

I partly wanted to put this out there for some opinions on what y'all think it could be. I also put it out there because in all my searches, all the shuddering posts are related to the TSB and this does not seem to be that problem. I'll post what my local dealer says and let you know if that fixes it, or if it continues.

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[Rp930]

Could be bad fuel, could be a bad coil, could be a lot of things. Did you fill up anywhere that was iffy? is the check engine light back on.

 

[SILK]

Could be bad fuel, could be a bad coil, could be a lot of things. Did you fill up anywhere that was iffy? is the check engine light back on.

I filled up at my local Wawa, which is extremely busy and I've never had any issues with in the past. I also re-filled up from half a tank at a Gulf that was also extremely busy. Check engine light only came on when the initial shudder happened. I don't think I got to the brake fast enough before it went into its fault state. Hasn't come back on since.

Edit: I'm at half a tank again. I could fill it up once more, but I wasn't sure if that was a good idea since the dealer may want to drain it to put a little in and see what happens. Should I try filling it back up again first? What about an additive like HEET that'll get rid of any existing water in the fuel?

 

[y2krtaf]

If the light came on,what code did you get?

 

[SILK]

If the light came on,what code did you get?

I don't know the exact code number, if that's what you're looking for. But the message in FordPass says "the Powertrain Control Module has detected an engine misfire condition caused by poor fuel quality or a powertrain malfunction. This can result in excessive exhaust temperatures that could damage the catalytic converter or other vehicle components." Again, I tried adding more fuel, but the issue persisted. I'm at half a tank now and can add more, but I don't want to fill it with fuel if the dealer might empty it out anyway. Unless the group is fairly certain that's the issue. I know it says "poor fuel quality" but it also gives the extremely vague "or a powertrain malfunction."

 

[Rp930]

Heet is ok just don’t get carried away. I would probably try to run that tank out as long as the Check light is not on. Then try new fuel. If the light comes on take it in.

 

[SILK]

Heet is ok just don’t get carried away. I would probably try to run that tank out as long as the Check light is not on. Then try new fuel. If the light comes on take it in.

This was my plan, but I have been concerned of damaging the engine if there indeed is water or something in the fuel. It'll take me another week or so of driving before the tank is empty.

 

[Rp930]

If the misfire is still there I would take it in now Or try Heet for a 20 or 30 miles. If it’s going to work you should know by then.

 

[P. A. Schilke]

I don't know the exact code number, if that's what you're looking for. But the message in FordPass says "the Powertrain Control Module has detected an engine misfire condition caused by poor fuel quality or a powertrain malfunction. This can result in excessive exhaust temperatures that could damage the catalytic converter or other vehicle components." Again, I tried adding more fuel, but the issue persisted. I'm at half a tank now and can add more, but I don't want to fill it with fuel if the dealer might empty it out anyway. Unless the group is fairly certain that's the issue. I know it says "poor fuel quality" but it also gives the extremely vague "or a powertrain malfunction."

Hi Silk,

Trying to get my head around this problem but nothing makes sense other than bad fuel or a bad battery with low voltage causing the PCM to go weird.... Hope the dealer can fix this.

Best,
Phil Schilke
Ranger Vehicle Engineering
Ford Motor Co. Retired

 

[SILK]

If the misfire is still there I would take it in now.

I have an appointment for tomorrow.

Hi Silk,

Trying to get my head around this problem but nothing makes sense other than bad fuel or a bad battery with low voltage causing the PCM to go weird.... Hope the dealer can fix this.

Best,
Phil Schilke
Ranger Vehicle Engineering
Ford Motor Co. Retired

Thanks Phil. Your input on this forum has answered so many of my general questions. I'm certainly grateful you're here. We'll see what the dealer says tomorrow.

 

[y2krtaf]

I don't know the exact code number, if that's what you're looking for. But the message in FordPass says "the Powertrain Control Module has detected an engine misfire condition caused by poor fuel quality or a powertrain malfunction. This can result in excessive exhaust temperatures that could damage the catalytic converter or other vehicle components." Again, I tried adding more fuel, but the issue persisted. I'm at half a tank now and can add more, but I don't want to fill it with fuel if the dealer might empty it out anyway. Unless the group is fairly certain that's the issue. I know it says "poor fuel quality" but it also gives the extremely vague "or a powertrain malfunction."

Yes,was curious if you knew the specific code that was set.

 

[SILK]

I would agree with Phil on the possible bad battery. / charging issue. Only because you have two problems that seem linked at this point

Regardless of shot in the dark diagnosis on here, you need active and current mechanics diagnosing with the right equipment. This is beyond some water in your fuel im sure.

It's at the dealer as we speak. According to FordPass, they took it for a 5mi test drive this morning. Hoping they confirmed the issue. FordPass isn't indicating it's been moved otherwise. I'll definitely update when I hear more. Hoping to get a call within the next hour.

 

[SILK]

Dealer Update:

They drove it 5 miles, immediately noticed the issue and found that one of the spark plug coils was bad. Apparently the plug was bad too. They found water(???) in the boot(?) of that coil. Ordering a new plug and coil. Should have it back in a couple days. Adding some dielectric grease to hopefully prevent that from happening again.

 

[P. A. Schilke]

Dealer Update:

They drove it 5 miles, immediately noticed the issue and found that one of the spark plug coils was bad. Apparently the plug was bad too. They found water(???) in the boot(?) of that coil. Ordering a new plug and coil. Should have it back in a couple days. Adding some dielectric grease to hopefully prevent that from happening again.

Hi Silk,

Any explanation of the infotainment screen going blank? Seems to me the coil/plug is not related to that even of a blank screen.

Best,
Phil Schilke
Ranger Vehicle Engineering
Ford Motor Co. Retired

 

[SILK]

Hi Silk,

Any explanation of the infotainment screen going blank? Seems to me the coil/plug is not related to that even of a blank screen.

Best,
Phil Schilke
Ranger Vehicle Engineering
Ford Motor Co. Retired

Phil,

No explanation as of yet. Phil, do you think I will see any lasting damage from driving the truck with the malfunctioning coil/plug? I had to drive it about 250 miles to get home. As I said, I was able to get around the shudder by manually shifting, but I'm assuming the plug was firing throughout the entire rev range and it was just most noticeable during those lower RPM's. I still have 4 years and 53,000 miles to go on my warranty, but I'm concerned with water being near the plug and the fact that it was damaged and I had to continue to drive it. I was 40 miles from the nearest dealer, which I stopped at on my way home and they said it was OK to drive.

Silk

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