Check engine light flashing - Cylinder 6 low compression

[Poppavein]

My first guess was a lean condition, perhaps caused by a bad injector. But I suppose there are other ways that could cause a lean condition.

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[Roach011]

If there was no issues inside the cylinders, the other thing to worry about would be the catalytic. Lean burn means higher than normal temps, and possibly turbo bearings (although those are usually pretty obvious).

I'd be questioning why it ran so lean - unless you already know the answer to that one and just don't want to say it out loud.

No I don't actually and the dealer already accused me of using a tuner, which I haven't - for this exact reason mind you. That is my chief concern.

 

[Ducati1098]

Got an update from the dealer - burned valve from running lean. no piston or cylinder damage, calling for a head replacement. All covered under warranty, looking into parts availability now. I'm supposed to talk to the actual tech at some point today. Anything specific I should ask? I'm mostly concerned about down stream effects of running lean for who knows how long.

Hmm lean enough to burn a valve, but not for any type of warning or check engine light. These engines are pretty well monitored. Still seems odd, but oh well.
Do you have the rest of the freeze frame data from the picture you originally posted. From the fuel trims I can see on there, it wasn't really lean at all.

I would just make sure they check everything else like @Brian_B mentioned. Converter, turbo, ect.

 

[Snacktime]

Bad fuel injector?

 

[Roach011]

Hmm lean enough to burn a valve, but not for any type of warning or check engine light. These engines are pretty well monitored. Still seems odd, but oh well.
Do you have the rest of the freeze frame data from the picture you originally posted. From the fuel trims I can see on there, it wasn't really lean at all.

I would just make sure they check everything else like @Brian_B mentioned. Converter, turbo, ect.

I had a "powertrain malfunction/reduced power" on 1/21 and a check engine light on 2/7 calling out misfire prior to this. Both of those previous issues went away on their own, same day. Vehicle never ran different or poorly until the day I posted here on 2/14.

I unfortunately don't have the full screen shot.

 

[Ducati1098]

I had a "powertrain malfunction/reduced power" on 1/21 and a check engine light on 2/7 calling out misfire prior to this. Both of those previous issues went away on their own, same day. Vehicle never ran different or poorly until the day I posted here on 2/14.

I unfortunately don't have the full screen shot.

Yeah idk. Too hard to say without seeing all the data. But it really doesn't matter now anyway. I would just let them replace the head and hopefully everything is good afterwards.

 

[Roach011]

Yeah idk. Too hard to say without seeing all the data. But it really doesn't matter now anyway. I would just let them replace the head and hopefully everything is good afterwards.

for sure. the questions now are logistical more than pretty much anything else.

 

[Roach011]

Yeah idk. Too hard to say without seeing all the data. But it really doesn't matter now anyway. I would just let them replace the head and hopefully everything is good afterwards.

spoke with the tech that did the diag. They are convinced I put a tuner on the bronco and that's why its running lean. For the record - i did not.

Is there any way you could accidentally adjust the PCM fuel management settings in forscan? Is that even a thing?

They said the bronco only had 6 start cycles on it when the started diag - does clearing dtc codes w/ forscan reset that tracker?

Tech had no answer for why the motor never alerted to lean fuel, other than tuner.

 

[Ducati1098]

spoke with the tech that did the diag. They are convinced I put a tuner on the bronco and that's why its running lean. For the record - i did not.

Is there any way you could accidentally adjust the PCM fuel management settings in forscan? Is that even a thing?

They said the bronco only had 6 start cycles on it when the started diag - does clearing dtc codes w/ forscan reset that tracker?

Tech had no answer for why the motor never alerted to lean fuel, other than tuner.

Forscan cannot change anything with the PCM.

Even if you did have an aftermarket tune, the ones on the market (other then a full custom tune) are extremely safe in regards to fuel/timing and all that, so that wouldn’t cause a cylinder to go lean.

6 ignition cycles is very odd, clearing codes will not reset it. As far as I’m aware, the only thing that will is reprogramming the PCM. Did you have any OTA updates or have the PCM updated recently at all?

Either way, that’s not proof that it ever had a programmer on it or not. So don’t let them try and tell you it’s not warranty because of that number.

 

[Roach011]

Forscan cannot change anything with the PCM.

Even if you did have an aftermarket tune, the ones on the market (other then a full custom tune) are extremely safe in regards to fuel/timing and all that, so that wouldn’t cause a cylinder to go lean.

6 ignition cycles is very odd, clearing codes will not reset it. As far as I’m aware, the only thing that will is reprogramming the PCM. Did you have any OTA updates or have the PCM updated recently at all?

Either way, that’s not proof that it ever had a programmer on it or not. So don’t let them try and tell you it’s not warranty because of that number.

Thank you for that. The only thing I can think of is the shop that initially did the diag might have? But I'm not aware of any updates or reprogramming. The tech did not have a good answer for the engine not logging or alerting to lean fuel, maybe there is an electrical gremlin not logging or monitoring properly?

They are doing everything under warranty so no issues there.

 

[Ducati1098]

Thank you for that. The only thing I can think of is the shop that initially did the diag might have? But I'm not aware of any updates or reprogramming. The tech did not have a good answer for the engine not logging or alerting to lean fuel, maybe there is an electrical gremlin not logging or monitoring properly?

They are doing everything under warranty so no issues there.

Yeah that’s interesting. Without seeing the freeze frame it’s difficult to say what went wrong. Even with that it might not be possible to tell. Glad to hear they’re covering it regardless

 

[Roach011]

Yeah that’s interesting. Without seeing the freeze frame it’s difficult to say what went wrong. Even with that it might not be possible to tell. Glad to hear they’re covering it regardless

Thank you for the insight and help! Been incredibly valuable

 

[Roach011]

Yeah that’s interesting. Without seeing the freeze frame it’s difficult to say what went wrong. Even with that it might not be possible to tell. Glad to hear they’re covering it regardless

in case you're curious - spent about 20 minutes with the tech in the shop Friday.

 

[Spooled]

definitely looks like a burned up valve to me.

I wouldn't get a warm and fuzzy feeling with them just slapping on a new head and sending me on my way without a proper root cause analysis.

 

[Roach011]

definitely looks like a burned up valve to me.

I wouldn't get a warm and fuzzy feeling with them just slapping on a new head and sending me on my way without a proper root cause analysis.

Agreed - Ford comped me 36k miles of their premium warranty so i have that through 88k miles. I'll be making a decision over the next year as to my future with the Bronco (and ford maybe). Time will tell.

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