Idle goes rough randomly. Stock tune..

Discussion in 'Issues, Repairs, Warranty, TSB, Recalls' started by Andy13186, Dec 21, 2019.

  1. Andy13186

    Andy13186 Well-Known Member

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    Hey guys, Ive had a problem for quite a while and havent been able to figure it out. When my car is hot and idling every once in a while the idle will go rough and the car will almost stall. Its actually stalled twice. I had run an e85 tune for a while before this problem started and then I got a check engine light for an o2 sensor. I put the stock tune back on and ran 93 for a while but the o2 sensor light came back on, so I had that fixed by the dealer like 8 months ago. On the drive back from the dealer the idle went rough and the car stalled while running 93 and the stock tune. I expected the check engine light to come back on again but it didnt for like 8 months and my car kept going rough randomly so I used some fuel injector cleaner, Seafoam, Marvel Mystery oil and everything just to make sure the fuel system was clean. Then the light came on for the other side o2 sensor so I replaced that myself. The light is off now but I still have my idle going rough randomly and I have no idea why. Has anyone else had this problem? The car is on the stock tune and I run shell 93 octane. The only mods I have are electric cutouts near the mufflers and a K&N air filter..

    If anyone has had this problem and knows of a solution, or if anyone has any suggestions that would be much appreciated. I dont really know what to do.. Kind of stressful having your idle go rough right before pulling out into traffic.

    Other than the idle going rough randomly for a few seconds while the car is hot the car runs great..
     
  2. BlackandBlue

    BlackandBlue Well-Known Member

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    I would have the dealer look at the IMRC system.

    12:1 engines idle terribly. The IMRC System is used for idle consistency on this high compression engine.
     
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  3. thelostotter

    thelostotter Well-Known Member

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    Have you cleaned the MAF sensor? If the K&N filter oil got on there it could be causing issues like you describe.
     
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  4. natepcbfl

    natepcbfl Well-Known Member

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    I had an issue with stumbling idle. Ended up being VCT solenoids.
    img_0240-jpg.jpg
    upload_2019-12-23_8-7-18.png
     
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    Andy13186

    Andy13186 Well-Known Member

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    I bought some maf sensor cleaner, I will try that as soon as I get it in the mail.

    They changed my cam phaser solenoids and cam phasers already, but that did nothing for me. I forgot to mention that because the reason they replaced the phasers was for the bbq tick and a light rev rattle, which the phasers didnt fix either. I dont think the issue started after the phasers but I am not 100% sure so this may be a possibility.

    Was your idle constantly stumbling or did it just go rough for like 5 seconds every once in a while. Mine is fine and smooth 99.9% of the time, I have been trying to get it on camera but it never seems to do it while I'm filming.
     
  6. natepcbfl

    natepcbfl Well-Known Member

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    I was having slight issues at first when coming to a stop where it would be ok then stumble and sometimes die. I did all the standard "tune up" stuff, plugs, filters, clean MAF, ect ect and it didnt fix it. Then it got worse where it would do it while it was just sitting still and started to die constantly unless i feathered the gas (it did seem to be when it was warmed up). It took about 10k miles before it got to the bad point doing it constantly. Found previous year coyote's with the same issue pointing at the solenoids. Read a few things and narrowed it down to try replacing the VCT solenoids since it was an easy DIY $100 try. Front reading reports it sounds like they may get gummed up after some time or the oil passages in them maybe getting blocked a little. As you said driving it was fine and no issues or performance loss. One thing about changing them I will mention is the passenger side rear bolts for the valve covers are a bitch to get to.
     
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    Andy13186

    Andy13186 Well-Known Member

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    Finally caught it going rough and stalling on camera. This was after about a 25 minute drive I was just sitting there at a red light and it went rough then turned off. 3rd time its actually stalled total, in about 8k miles. Lucky to get it on film.

     
  8. natepcbfl

    natepcbfl Well-Known Member

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    That's exactly what mine was doing. Here is what it was like when it first started to regularly stumble when I came to a stop and was able to get a video. Up until this it was so irregular that it would even go a few days with no issue. Within a month or two of the video I would have to feather the gas when I came to a stop or it would die, even if I let it just sit idle it would eventually die in the driveway (but not right after startup). Seems like the worst was when it was driving and then had to come to a stop and it had to regulate idle.
    - 34sec stumble / 43sec almost died.
     
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  9. Dana Pants

    Dana Pants Well-Known Member

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    I have the same issue. If you find a solution, post it up.
     
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    Andy13186

    Andy13186 Well-Known Member

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    I got my car back from my dealer today, they did a "Misfire neutral correction profile relearn" so far so good but I cant yet confirm that this was the solution since lack of time
     
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    Andy13186

    Andy13186 Well-Known Member

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    My idle went a bit rough twice today so I dont think their attempted fix worked.
     
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    Andy13186

    Andy13186 Well-Known Member

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    Got my car back from the dealer again, they did :

    TeM60J9.jpg

    So far the car hasnt gone rough again or stalled but ive only had it back for a few days.

    So I do think the VCT solenoids were to blame at this time.
     
  13. fahadco80

    fahadco80 Member

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    Hope it stays this way, good luck

    Please keep us updated if any thing goes wrong
     
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  14. fahadco80

    fahadco80 Member

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    By the way, mine did not make any idling issues after taking it from the dealer (they only did a reset) but yesterday it stalled when coming to red light, and today the RPM fluctuation came back when I came to red light but without stalling.

    I am also having the rattle snake noise at 2k, this is not acceptable, I am not sure why Ford isn't making a move...!!!!

    The problem with me that here in my country we only have one dealer and we do not have the buyback program like in the US

     
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    Andy13186

    Andy13186 Well-Known Member

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    Yea mines got that same exact same noise they checked it out, thats what I called the flutter. They said its normal. I also have the 2k rattle and they say its normal too. I am not too worried about those. For me the flutter noise goes away somewhat once the car is warm, and when I drive with paddles active it doesnt seem to do it. I drive with paddles active most of the time once the car is warm.

    But for the stalling and rough idle this VCT solenoid fix seems to have resolved my issue so far, no problems since I got the car back.
     
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