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Engine Misfire / Harness Issues (vote modded only if tuned)

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Discussion Starter · #1 · (Edited)
The Official Misfire / Engine Harness/ Random CELs Issue Thread for 2.0 EB

Ok,

So there are many threads on here about Misfires and General Engine Harness issues and Random CELs, lets try and get this organized.

To those that have these issues, Lets do a Vote and Comment ONLY if you have misfire and harness issues. Leave Details Below and we will keep them together. Before you leave comments, make sure to give all information. Please do not Deviate from this. All this will be kept together.


Year:
ST 1, 2, or 3:
Miles on vehicle when issue started:
Miles on vehicle currently:
How far into vehicle ownership (time):
Modifications:
If modified with tune, what tune:
Was premium fuel used:
Was issue covered under warranty:
Steps taken under warranty to resolve issue:
Steps taken not under warranty to resolve issue:
Was the issue Resolved?
Any other Comments.
 

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Discussion Starter · #2 · (Edited)
CVPI
Year:2015
ST 1, 2, or 3:1
Miles on vehicle when issue started:2000
Miles on vehicle currently:6400
How far into vehicle ownership (time): 6 Months
Modifications: None
If modified with tune, what tune: N/A
Was premium fuel used: Always, 93 Shell or BP
Was issue covered under warranty: Yes / Still pending
Steps taken under warranty to resolve issue: New MAP Sensor (x3) New ECT (x2) Wiring overlays on Factory Harness, Ect...
Steps taken not under warranty to resolve issue: Wiggle Test for diagnosis
Was the issue Resolved?: No
Any other Comments: Ford Approved new harness and sent out field service engineer as of 5/24. Car has been in the dealer for 2 months now. Update: Well.. they finally replaced the harness in mine, going to pick up tonight. A field service engineer drove my car for 100 milles or so supposedly.
NICKP
Year: 2015
ST 1, 2, or 3: ST3
Miles on vehicle when issue started: 7400
Miles on vehicle currently: 19.5k
How far into vehicle ownership (time): 22 months
Modifications: Cobb cat back
If modified with tune, what tune: no tune
Was premium fuel used: 93 octane 100% gasoline (no ethanol blend fuels ever)
Was issue covered under warranty: yes
Steps taken under warranty to resolve issue: Reprogram PCM x3; coils; plugs multiple times, bore scope for carbon, compression test, power balance test - all inconclusive.
Steps taken not under warranty to resolve issue: N/A
Any other Comments.

Hawkeye18
Year: 2014
ST 1, 2, or 3: 3
Miles on vehicle when issue started: ~5,000
Miles on vehicle currently: 17,121 (yes, I know, that's barely any lol)
How far into vehicle ownership (time): 2.5 yrs
Modifications: Shifter engine bracket bushings
If modified with tune, what tune: N/A
Was premium fuel used: 93 only
Was issue covered under warranty: No ("could not duplicate")
Steps taken under warranty to resolve issue: N/A
Steps taken not under warranty to resolve issue: Fixed it my damn self
Was the issue Resolved? YES
Any other Comments.
My issues weren't as bad as some I've seen, but I had frequent stumbling when letting off the throttle at low speeds, and what turned out to be fairly significant slight-throttle power loss. I ended up performing the repair myself as per the video on youtube, and all of the issues have disappeared. I wasn't expecting any more power, but was surprised to find out that I'd been losing quite a bit - the amount of throttle i had to give the car from a stop to keep the engine from stumbling now caused me to nearly break the tires loose. I suspect the TPS had been reading low. The car is now much more driveable in puttering-around-town regimes.

Devourer

ST 1, 2, or 3: ST2
Miles on vehicle when issue started: 15,500
Miles on vehicle currently: 20,500
How far into vehicle ownership (time): 7 months
Modifications: N/A
If modified with tune, what tune:
Was premium fuel used: 91 octane
Was issue covered under warranty: YES
Steps taken under warranty to resolve issue: First dealer couldn't find issue, car is currently sitting at another dealer.
Steps taken not under warranty to resolve issue:
Was the issue Resolved? NO
The check engine light has been on for the third time since I purchased my 15' ST as a CPO. Currently the
car is at the dealer and I'm waiting for updates. This is my first ford and I never expect to experience such a problem.

KZON86

Year: 2016
ST 1, 2, or 3: ST2
Miles on vehicle when issue started: 5,800
Miles on vehicle currently: 16,000
How far into vehicle ownership (time): 2-3 months
Modifications: None
If modified with tune, what tune:
Was premium fuel used: Yes
Was issue covered under warranty: Yes
Steps taken under warranty to resolve issue: Code indicated misfire in cylinder 3. Dealer swapped coil packs between #3 and #4 cylinders to see if the problem followed the coil. The CEL code was cleared and has not come on since. Service performed at 12,500 miles.
Steps taken not under warranty to resolve issue:
Was the issue Resolved? Unknown
Any other Comments.
Multiple dealers related this problem to Special Service Message 45856. " Some 2015-2016 Focus ST models may exhibit MIL On with perceived misfire after cold start."
One dealer reported the code indicated the misfire occurred in the first 1000 revolutions.
My MIL light would be on 80% of start ups and this would occur regardless of temperature or humidity outside.No driveablilty issues, but the car continues to exhibit a slightly rough idle.
CALIJOE
Year: 2016
ST 1, 2, or 3: ST1
Miles on vehicle when issue started: 500
Miles on vehicle currently:10000
How far into vehicle ownership (time): 9 Month's
Modifications: None when it started.
If modified with tune, what tune: Stratified now.
Was premium fuel used: Yes 91
Was issue covered under warranty: If they ever get a fix I'll take it in.
Steps taken under warranty to resolve issue: N/A
Steps taken not under warranty to resolve issue: N/A
Was the issue Resolved? See next column.
Any other Comments. I voted 2016 only, because it wasn't modded when it started happening. I only had the idle dip but ever since I got my tune I haven't had an issue. I think the idle dip has something to do with the charge temp and now that the shutters are disabled I haven't had a problem. Before, the charge temps were 25 to 30 deg. higher the ambient, now there the same unless your getting on it of course.
xrayruester
Year:. 2015
ST 1, 2, or 3: ST3
Miles on vehicle when issue started: ~15,000 miles car started to run rough after cold start, more so when the temperature was cold.
Miles on vehicle currently:. 16,900, also at the point that I got my first cel for a P0300 random misfire
How far into vehicle ownership (time): about a year and a half
Modifications:. Intake, exhaust, short throw, intercooler.
If modified with tune, what tune:. No tune
Was premium fuel used:. Always used 93, occasionally used 91 when traveling.
Was issue covered under warranty: so far the plan is to cover under warranty. Shop still has my car as they fried the BCM during a recall for the hatch. Car has been at the dealer for a week as the part is on backorder. They cannot look into the cell as the car is bricked. They will see what they can do after they get a new BCM.
Steps taken under warranty to resolve issue:. Nothing as of yet, car is a paper weight.
Steps taken not under warranty to resolve issue: regap spark plugs, switched spark plugs between oem, Denso, NGK, and back to oem. Took intake and intercooler off as well, car still runs rough at idle with the occasional idle hunting and random stalling/rpm drop.
Was the issue Resolved? Nope, still sitting at the shop unable to be diagonsed until they get a working BCM.
Any other Comments.
So far the car has been great until the weather got cold this year. Car has progressively gotten worse since then and it is rather disheartening. Especially when you throw the fact that the dealer also fired my bcm and cannot do anything until a backordered part shows up. So, I'm not expecting my car back for sometime. Prognosis looks grim.
HBgeek
Year: 2015
ST 1, 2, or 3: ST1
Miles on vehicle when issue started: 31
Miles on vehicle currently: 26,800
How far into vehicle ownership (time): 1 year 8 months
Modifications: Exhaust, DryFlow Filter, Short Shift Plate, FMIC, Tune
If modified with tune, what tune: Stratified OTS 91 octane
Was premium fuel used: 91 octane
Was issue covered under warranty: Yes
Steps taken under warranty to resolve issue: PCM flash, then all fuel injectors replaced.
Steps taken not under warranty to resolve issue: N/A
Was the issue Resolved? Yes (Seemingly)
Any other Comments. I had my first CEL pop up around 5K miles. Then close to 10k it came on and stayed on and I pulled the random misfire code. I took it to the dealer after returning the car to stock except for the exhaust. They flashed the PCM and it came back a week later on a cold start up as usual. The next visit they said I had "rust" on my injectors and they replaced all of them. There was also some fluid in my spark plug wells. Ever since then I have not had the CEL return. I have put on around 17k miles since then and I am not sure if my stratified tune has anything to do with it or not. I believe I was still Cobb tuned at the time the CEL came on though.

LUCS_ST
Year: 2016
ST 1, 2, or 3: ST3 (Canada)
Miles on vehicle when issue started: 21981km
Miles on vehicle currently: 34000km
How far into vehicle ownership (time): 7 months
Modifications: NON
If modified with tune, what tune:
Was premium fuel used: 91 minimum
Was issue covered under warranty: YES
Steps taken under warranty to resolve issue: regular diagnostic, coils, plug, injector swap, resets
Steps taken not under warranty to resolve issue: NON
Was the issue Resolved? NO, escalated to Ford engineering
Any other Comments. I've had at least 6 CEL related to the issue. Seems like the problem is getting worse with time and time between CEL is getting shorter every time

UPDATE: received a call from my dealer (service manager) yesterday. He finally spoke to ford engineering and they are currently testing multiple engines to understand the cause. They have pinpointed the problem to an over sensitivity issue. The system is detecting what it thinks is a misfire on cold start and starts correcting itself prematurely; this is propagated over time which eventually triggers the CEL. They are trying to reduce the sensitivity programming so that I doesn't detect a misfire that is non existent. its more complicated than that, but its how it was explained to me. He was meeting the engineering team yesterday to get a status and expected ETA. More to come.

SK_ST3
Year: 2015
ST 1, 2, or 3: st3
Miles on vehicle when issue started: 29000km
Miles on vehicle currently: 30400
How far into vehicle ownership (time):
Modifications: 1 year 8 months
If modified with tune, what tune: stratified tuned on 94 octane
Was premium fuel used: 94
Was issue covered under warranty: yes
Steps taken under warranty to resolve issue: new long block, injectors, reprogramming pcm numerous times. Waiting for fse to update dealer on next steps to take.
Steps taken not under warranty to resolve issue: replaced spark plugs with itv24 gapped at 0.026" and replaced all 4 coil packs.
Was the issue Resolved? Not yet.
Been 3 months now without the car, starting to get tiresome of this but the dealership is working hard at finding a solution
 

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answers in blue:

Year: 2015
ST 1, 2, or 3: ST3
Miles on vehicle when issue started: 7400
Miles on vehicle currently: 19.5k
How far into vehicle ownership (time): 22 months
Modifications: Cobb cat back
If modified with tune, what tune: no tune
Was premium fuel used: 93 octane 100% gasoline (no ethanol blend fuels ever)
Was issue covered under warranty: yes
Steps taken under warranty to resolve issue: Reprogram PCM x3; coils; plugs multiple times, bore scope for carbon, compression test, power balance test - all inconclusive.
Steps taken not under warranty to resolve issue: N/A
Any other Comments.
 

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Discussion Starter · #4 ·
answers in blue:

Year: 2015
ST 1, 2, or 3: ST3
Miles on vehicle when issue started: 7400
Miles on vehicle currently: 19.5k
How far into vehicle ownership (time): 22 months
Modifications: Cobb cat back
If modified with tune, what tune: no tune
Was premium fuel used: 93 octane 100% gasoline (no ethanol blend fuels ever)
Was issue covered under warranty: yes
Steps taken under warranty to resolve issue: Reprogram PCM x3; coils; plugs multiple times, bore scope for carbon, compression test, power balance test - all inconclusive.
Steps taken not under warranty to resolve issue: N/A
Any other Comments.
Was the issue Resolved?
 

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Year: 2014
ST 1, 2, or 3: 3
Miles on vehicle when issue started: ~5,000
Miles on vehicle currently: 17,121 (yes, I know, that's barely any lol)
How far into vehicle ownership (time): 2.5 yrs
Modifications: Shifter engine bracket bushings
If modified with tune, what tune: N/A
Was premium fuel used: 93 only
Was issue covered under warranty: No ("could not duplicate")
Steps taken under warranty to resolve issue: N/A
Steps taken not under warranty to resolve issue: Fixed it my damn self
Was the issue Resolved? YES

Any other Comments.

My issues weren't as bad as some I've seen, but I had frequent stumbling when letting off the throttle at low speeds, and what turned out to be fairly significant slight-throttle power loss. I ended up performing the repair myself as per the video on youtube, and all of the issues have disappeared. I wasn't expecting any more power, but was surprised to find out that I'd been losing quite a bit - the amount of throttle i had to give the car from a stop to keep the engine from stumbling now caused me to nearly break the tires loose. I suspect the TPS had been reading low. The car is now much more driveable in puttering-around-town regimes.
 

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Year 2015
ST 1, 2, or 3: ST2
Miles on vehicle when issue started: 15,500
Miles on vehicle currently: 20,500
How far into vehicle ownership (time): 7 months
Modifications: N/A
If modified with tune, what tune:
Was premium fuel used: 91 octane
Was issue covered under warranty: YES
Steps taken under warranty to resolve issue: First dealer couldn't find issue, car is currently sitting at another dealer.
Steps taken not under warranty to resolve issue:
Was the issue Resolved? NO

The check engine light has been on for the third time since I purchased my 15' ST as a CPO. Currently the
car is at the dealer and I'm waiting for updates. This is my first ford and I never expect to experience such a problem.
* update, forgot the mention the year
 

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Year: 2016
ST 1, 2, or 3: ST2
Miles on vehicle when issue started: 5,800
Miles on vehicle currently: 16,000
How far into vehicle ownership (time): 2-3 months
Modifications: None
If modified with tune, what tune:
Was premium fuel used: Yes
Was issue covered under warranty: Yes
Steps taken under warranty to resolve issue: Code indicated misfire in cylinder 3. Dealer swapped coil packs between #3 and #4 cylinders to see if the problem followed the coil. The CEL code was cleared and has not come on since. Service performed at 12,500 miles.
Steps taken not under warranty to resolve issue:
Was the issue Resolved? Unknown
Any other Comments.

Multiple dealers related this problem to Special Service Message 45856. " Some 2015-2016 Focus ST models may exhibit MIL On with perceived misfire after cold start."

One dealer reported the code indicated the misfire occurred in the first 1000 revolutions.

My MIL light would be on 80% of start ups and this would occur regardless of temperature or humidity outside.No driveablilty issues, but the car continues to exhibit a slightly rough idle.
 

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Discussion Starter · #8 ·
ST 1, 2, or 3: ST2
Miles on vehicle when issue started: 15,500
Miles on vehicle currently: 20,500
How far into vehicle ownership (time): 7 months
Modifications: N/A
If modified with tune, what tune:
Was premium fuel used: 91 octane
Was issue covered under warranty: YES
Steps taken under warranty to resolve issue: First dealer couldn't find issue, car is currently sitting at another dealer.
Steps taken not under warranty to resolve issue:
Was the issue Resolved? NO

The check engine light has been on for the third time since I purchased my 15' ST as a CPO. Currently the
car is at the dealer and I'm waiting for updates. This is my first ford and I never expect to experience such a problem.
What year Devourer?

Sent from my SM-G930P using Tapatalk
 

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Year: 2016
ST 1, 2, or 3: ST1
Miles on vehicle when issue started: 500
Miles on vehicle currently:10000
How far into vehicle ownership (time): 9 Month's
Modifications: None when it started.
If modified with tune, what tune: Stratified now.
Was premium fuel used: Yes 91
Was issue covered under warranty: If they ever get a fix I'll take it in.
Steps taken under warranty to resolve issue: N/A
Steps taken not under warranty to resolve issue: N/A
Was the issue Resolved? See next column.
Any other Comments. I voted 2016 only, because it wasn't modded when it started happening. I only had the idle dip but ever since I got my tune I haven't had an issue. I think the idle dip has something to do with the charge temp and now that the shutters are disabled I haven't had a problem. Before, the charge temps were 25 to 30 deg. higher the ambient, now there the same unless your getting on it of course.
 

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Year:. 2015
ST 1, 2, or 3: ST3
Miles on vehicle when issue started: ~15,000 miles car started to run rough after cold start, more so when the temperature was cold.
Miles on vehicle currently:. 16,900, also at the point that I got my first cel for a P0300 random misfire
How far into vehicle ownership (time): about a year and a half
Modifications:. Intake, exhaust, short throw, intercooler.
If modified with tune, what tune:. No tune
Was premium fuel used:. Always used 93, occasionally used 91 when traveling.
Was issue covered under warranty: so far the plan is to cover under warranty. Shop still has my car as they fried the BCM during a recall for the hatch. Car has been at the dealer for a week as the part is on backorder. They cannot look into the cell as the car is bricked. They will see what they can do after they get a new BCM.
Steps taken under warranty to resolve issue:. Nothing as of yet, car is a paper weight.
Steps taken not under warranty to resolve issue: regap spark plugs, switched spark plugs between oem, Denso, NGK, and back to oem. Took intake and intercooler off as well, car still runs rough at idle with the occasional idle hunting and random stalling/rpm drop.
Was the issue Resolved? Nope, still sitting at the shop unable to be diagonsed until they get a working BCM.
Any other Comments.

So far the car has been great until the weather got cold this year. Car has progressively gotten worse since then and it is rather disheartening. Especially when you throw the fact that the dealer also fired my bcm and cannot do anything until a backordered part shows up. So, I'm not expecting my car back for sometime. Prognosis looks grim.
 

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No, presently unresolved. Service department said to make an appointment when the MIL illuminates again in the future. They admitted Ford has not yet released the fix for this problem.
Which is insane, as this issue looks to be over 2 years old now. It also appears to be an issue with the mustang ecoboost and the RS as well.
 

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Which is insane, as this issue looks to be over 2 years old now. It also appears to be an issue with the mustang ecoboost and the RS as well.
Don't even get me started.

I initiated my state's lemon law process a couple weeks ago. Got my first contact from Ford corporate today.
 

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Don't even get me started.

I initiated my state's lemon law process a couple weeks ago. Got my first contact from Ford corporate today.
Good luck, hopefully you get taken care of. I'm outside of lemon law in PA, so I would have to go after other avenues. So far this is my only instance of a cel for a misfire, but judging by all the posts on here this doesn't look like it'll be the last. 2015, check engine light after startup, random misfire p0300... Just fits the criteria too well.
 

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Discussion Starter · #15 ·
Hey, at least its just a misfire and not an issue with random codes and limp mode lol.
 

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Year: 2015
ST 1, 2, or 3: ST1
Miles on vehicle when issue started: 31
Miles on vehicle currently: 26,800
How far into vehicle ownership (time): 1 year 8 months
Modifications: Exhaust, DryFlow Filter, Short Shift Plate, FMIC, Tune
If modified with tune, what tune: Stratified OTS 91 octane
Was premium fuel used: 91 octane
Was issue covered under warranty: Yes
Steps taken under warranty to resolve issue: PCM flash, then all fuel injectors replaced.
Steps taken not under warranty to resolve issue: N/A
Was the issue Resolved? Yes (Seemingly)
Any other Comments. I had my first CEL pop up around 5K miles. Then close to 10k it came on and stayed on and I pulled the random misfire code. I took it to the dealer after returning the car to stock except for the exhaust. They flashed the PCM and it came back a week later on a cold start up as usual. The next visit they said I had "rust" on my injectors and they replaced all of them. There was also some fluid in my spark plug wells. Ever since then I have not had the CEL return. I have put on around 17k miles since then and I am not sure if my stratified tune has anything to do with it or not. I believe I was still Cobb tuned at the time the CEL came on though.
 

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Year: 2016
ST 1, 2, or 3: ST3 (Canada)
Miles on vehicle when issue started: 21981km
Miles on vehicle currently: 34000km
How far into vehicle ownership (time): 7 months
Modifications: NON
If modified with tune, what tune:
Was premium fuel used: 91 minimum
Was issue covered under warranty: YES
Steps taken under warranty to resolve issue: regular diagnostic, coils, plug, injector swap, resets
Steps taken not under warranty to resolve issue: NON
Was the issue Resolved? NO, escalated to Ford engineering
Any other Comments. I've had at least 6 CEL related to the issue. Seems like the problem is getting worse with time and time between CEL is getting shorter every time

UPDATE: received a call from my dealer (service manager) yesterday. He finally spoke to ford engineering and they are currently testing multiple engines to understand the cause. They have pinpointed the problem to an over sensitivity issue. The system is detecting what it thinks is a misfire on cold start and starts correcting itself prematurely; this is propagated over time which eventually triggers the CEL. They are trying to reduce the sensitivity programming so that I doesn't detect a misfire that is non existent. its more complicated than that, but its how it was explained to me. He was meeting the engineering team yesterday to get a status and expected ETA. More to come.
 

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Discussion Starter · #19 ·
Well.. they finally replaced the harness in mine, going to pick up tonight. A field service engineer drove my car for 100 milles or so supposedly.
 

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Let us know how it goes!
 
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