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Discussion Starter · #1 ·
NEW TO FORUM 2011 f150 3.5 with 88,000 on it. rough idle misfire/ slight hesitation going up hill with cruise

-changed plugs/ gapped to .030 (old ones were around .040 - .045
-changed coils/ swapped aroung with oem and accels
-cleaned cac and drilled weep hole this seemed to take care of up hill hesitation
-cleaned map and maf sensors besides the one on the intake which looked like it was baked oil.
-replaced pcv valve
- oil change with about 1000 miles on can smell gas in the oil

Still have misfire on idle and slight misfire when driving. any ideas? Also anyone done the manual valve cleaning? If so what were the before problems you had and the results? Thanks for your time!
 

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Pull and check your newly installed plugs. They are quite easy to crack the insulating porcelain resulting in your symptoms.
 
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Bravo Patrick, Bravo!

A new member/poster here decided to join and ask a question AFTER he had done research and AFTER he had already tried the fixes that have been known problem-solvers for a misfire.

I would try out what Elmore stated, also try doing a KAM reset.
 

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Discussion Starter · #4 ·
Thanks for the fast reply's Elmore and Milese! So i pulled the plugs again, could not see any cracks or carbon tracking, even went over them with a magnifying glass in case i missed something. forgot to mention kam reset has been done when i put the plugs in, then again when i put new coils in it, and the last time was when i cleaned all the sensors. Love the truck but this rough idle is killing me lol! Any other ideas? I appreciate your input!
 

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Didn't the 2011 and 2012's have a TSB for a faulty/problematic throttle body???
 

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Did you try the Idle Relearn? Not sure it would help with cruise issues. Seems these things have brain farts occasionally and need to relearn to walk. I do KAM, Throttle Cal, and Idle Relearn every couple of months just as a maintenance schedule for me. The first time I did Idle it smoothed things out and dropped it down about 100 rpm. Have also cleaned TB but can't say it improved anything...wasn't that dirty but did have some build up on back of plate.
 

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Discussion Starter · #7 ·
I did the idle relearn but not 100% I did it right, went for about 45 min drive which seemed to help as I was at a stop light the rpm gauge was not fluctuating nearly as bad as it was but could still feel the miss lighty.
 

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My 2011 has always had a rough idle compared to other vehicles I've owned. Even with fresh plugs. Been driving it 4+ years now and haven't had any misfires.

Are you sure it's a misfire? You will get codes for misfires. Torque pro or Sct devices can monitor each cylinder or total misfires.
 
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Discussion Starter · #9 ·
Did the throttle relearn today and all I can say is wow but yes it is definitely a misfire had my uncle plug his verus scan tool in it and he said there is definitely a misfires on all cylinders enough to idle rough but it has to do it so many times in a certain amount of time to throw the cel on. I had it into two different ford dealers and both said they couldn’t do anything about it because there was no cel light on. Truck has an extended warranty but basically they told me if there’s no codes they can’t touch it.
 

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Did the throttle relearn today and all I can say is wow but yes it is definitely a misfire had my uncle plug his verus scan tool in it and he said there is definitely a misfires on all cylinders enough to idle rough but it has to do it so many times in a certain amount of time to throw the cel on. I had it into two different ford dealers and both said they couldn’t do anything about it because there was no cel light on. Truck has an extended warranty but basically they told me if there’s no codes they can’t touch it.
If you're sure it's not plugs or coils, I wonder if maybe the timing chain is stretched enough to be causing the misfires.
One of the symptoms of a stretched timing chain will be a cold start rattle after a long (overnight) cold soak.
 

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Have you had a CEL come up yet? If so, details?

When i did my first plug change i either damaged one or got a defective plug. It would misfire under heavier throttle but wouldn't throw a code. Had to stay in the throttle and let it misfire constantly for a few seconds before the ECU recognized it and threw a code. Then i was able to determine what cylinder it was coming from.
 

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You won't throw a CEL until you exceed a misfire % based on RPM/Load Table data......read all about it in your OBD System Operation manual for your year-engine.....Misfire Monitor.....capture the data in the "Freeze Frame" picture that is stored for the CEL....not there to tell you there is a misfire...it is there to protect the Cat.:cool:
 

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Discussion Starter · #14 ·
Well I don’t think the timing chain is stretched as I have yet to hear that dreaded sound I’ve heard in many of the videos posted. Been below 0 the last week and haven’t really dug into anything else on it although I was able to get into mode $06 data and there are misfires showing on all cylinders ranging from about -15 to +15 which is pretty small but should be at zero if I understand correctly.
 

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Well I don’t think the timing chain is stretched as I have yet to hear that dreaded sound I’ve heard in many of the videos posted. Been below 0 the last week and haven’t really dug into anything else on it although I was able to get into mode $06 data and there are misfires showing on all cylinders ranging from about -15 to +15 which is pretty small but should be at zero if I understand correctly.
Did you ever work out your misfire problem?
 

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Discussion Starter · #16 ·
Did you ever work out your misfire problem?
Sorry i didnt reply sooner, I had never figured it out but I'm pretty sure as of 2 days ago I noticed the dreaded timing chain chatter on cold start up and has happened every morning since. Time to dig into that and see if that fixes the rough idle.
 

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I would also scope your manifold... see if you have carbon buildup on the top of your intake valves (valve coking), especially on the PCV side, causing a restriction of airflow to the cylinder.
 

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If you're sure it's not plugs or coils, I wonder if maybe the timing chain is stretched enough to be causing the misfires.
One of the symptoms of a stretched timing chain will be a cold start rattle after a long (overnight) cold soak.
It’s funny you say that I had a misfire on a 2015, took it to the dealer with the warranty they found two bad injectors and then realized that it’s possibly the timing chain stretch which they’re working on now.
 
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