Guys, been chasing a rough idle/stumble issue for a couple of weeks....finally took it to ford found that #4 was missing about 10% of the time. swapped the cop and put in a new plug as well. still ran rough...found that the connector wasnt making good contact.....is the clip that hooks to the coil pack replacable? any one have a part #? truck will run fine for a few minutes, then run like crap....new MAF, new tps air/fuel filter as well. thanks

 

My superduty has a slight miss after it rains you can tell it is loading up due to exhaust smell it will straighten up after it drys out but a heavy dew can cause it too

 

My truck is doing the same thing at 162000 miles, actually started a bit sooner...took to shop, no engine light and no codes, checked each cylinder and discovered coils were going bad on a few so replaced all and plugs....took back to shop( still doing the same thing) got it down to number 4 cylinder acting up....replaced fuel injector...still missing and sputtering mostly under load but it does seem to be intermitent better and worse at different times. Cant figure it out.

 

FYI, I could feel a miss and when scanned with AE it said Cylinder "I" (9) had a missfire and open circuit. So, I had a spare COPS and put a plug in it, then plugged the wire into it and grounded the spark plug and started it. Had spark, then stopped. The connector that plugs into the COP on Cyl. #9 had a broken wire inside the insulation about 1/2 inch behind the connector that plugs into the COPS.. I had to ohm it out back to the large harness connectors under the air filter housing. As an FYI, it is not the pargest connector that has the COPs signals, it is the smaller one below the larger one. BBe aware those wires down there are very faded from heat. Good luck.

 

Thanks for the info.....you know , I kinda thought about that and did some wire wiggling etc...but haven't put a meter to it...looks like a real pain to unravel all those wires.

 

Also, iw as doing some reading as I was surprised the Check Engine lamp was not on with those cosdes set. I guess because of our trucks GVRW they dumb down teh ECU not to set the CE light nearly as easy as a car or light truck. So, when Iw as trying to figure out which cylinder it was I had 3 COPS unplugged at a time running it with codes up the azz set and never got the CE light to come on. (and it does work) Same with my 02 Powerstroke F350. It wont set the CE with sensors unpluged very easy either.

 

For why no codes are set for misfires, read this:

https://www.ford-trucks.com/forums/5...t-come-on.html

Interesting info.

 

Well, put truck into what I thought was a descent auto shop early this morning and the guy tried to rip me a new one you might say.....Sheister all the way!!!!!! Woodlands Car Care in the Woodlands Tx. Tried to tell me that the 10 new spark plugs that I just put in were the wrong ones for my truck and they are motorcraft sp-479's which I called the Ford dealership and verified that they were indeed correct.( when I asked him what plugs were supposedly the right ones he couldnt tell me, he just said he didn't have the number????) Tried to tell me I needed a new coil for #4 cylinder but they switched coils out and there was no difference that the misfire didn't move( they are all new also)...So thats a lie I caught them in. Charged me for a compression check and didnt ok the price with me (tried to get 247.00 just for that) and got 99.00 for the diagnostics...the guy tried to tell me that fuel going down the intake at the fuel throttle body caused a hugh build up of carbon and that I needed to be totally cleaned out, when fuel only goes through at the injector points. (not to mention that throttle body had already been cleaned) then said gas tank needed to be cleaned. total he tried to get from me $1592.00 Can you believe that s**T......then he had the audacity to argue with me and try to make me feel bad, that he was only trying to help me so my truck wouldnt break down, didnt know how I was even driving the truck and that it could blow my transmission out (which is a standard by the way) All I went in for was diagonosed misfire on #4 that had already been determined to be the problem from another autoshop. My cousin who was with me at the time was about to come unglued......

Anyway, among other things he said my o2 sensors were bad and that there were 4 of them,(wanted to charge me $619.00 to fix that...LOL) but I have only managed to find 2, one on each side of the exhaust manifolds....looked furthur down and did not see any located aft of the Cat converter.
Can someone tell me how many there are? Thanks........

 

sounds like its time to find a better autoshop..

any reason why you didnt take it to a Ford dealer ??? they have the tools/equipement to make a proper repair if its a troublesome problem to find...

it might be more expensive then Joe's garage but at least they can def. find the issue..

 

The Ford dealer where I live at has a very bad reputation so I thought I was doing a smart thing by going to a local autoshop near me.....man was I wrong!

 

Your story reminds of few encounters I went thru with my EX.
I have only 2 o2 sensors ,if that helps.
As for Ford dealers ,they charge 110/hour here in Quebec just for good morning.

 

Only 2 O2 sensors for the F-series, 1999 through 2004, except possibly ones with California emissions.