Well a month ago I had my spark plugs changed. A few days after it started to misfire and the truck was shaking like a bad tire. Check Engine Light would flash then go away. Then it got worse and stayed on. Well took it back and the guy thought its probably a coil. Well that wasnt it. The code said misfire on cylinder 7. He said take it to this guy he knows alot about timing and I think maybe your timing is off. Well that guy said no its not that and my compression was good. He said its spark knocking and the only think that would cause a spark knock and a misfire was a fuel injector.

Well he replaced it and it ran good for a week. Last Saturday I was on a road trip to cedar point and luckily I was only 30 miles from home and it started to shake and act up again. The CEL would only flash and not allow me to pull a code. I turned around to get my dads truck. I called the guy and he said bring it in monday he is closed today. So I brought it to him and he couldnt get it to act up. Tuesday I call him and still nothing. So after work I went up there and I got it to act up but I had to beat the crap out of it to throw a code. It flashed and went away. He hooked his computer up and said it was still cylinder 7 misfiring. He was like Im going to have to think about this but my guess would be its the cam phaser on that side. Well I called him today and he said he is waiting on a gasket so he can put the valve cover back on. He is hoping that is the problem. My truck did have ticking noise but it has since I got it.

Do you think thats really what it is or could it be something else. Im getting sick of this. Its been in the shop 2.5 weeks in a months time. Just hoping this is the fix.

 

Sorry to say this but you need a new mechanic. He is just throwing parts on hoping he gets lucky. A phaser can't cause a misfire on one cylinder. He prob cracked the plug putting it in. I just hope he installs the phaser correctly or you will have bigger problems than a misfire.

 

My guess would be something to do w/ spark. Possiblty cracked the plug, or you have a coil going south..

 

Well the mechanic that did the plug change is not doing the cam phaser change. He referred me to him cause he had no idea what it could be. This guy did however install the fuel injector and it did run fine for about 2 weeks. Then he had no idea. He use to work at the local ford dealer than quit to open up his own shop. He did say they was alot of sludge built up on the valve cover. I run amsoil and I change my own oil which is leading me to think that the sludge is from the previous owner.

I could check the plug maybe its cracked. The guy that changed the plugs replaced the coil on cylinder 7 and it didnt make a difference. Thats why he referred me to this other mechanic. I guess I will find out tomorrow if its better or not.

 

Well here is an update. They put the truck back together this morning and its still acting up. He didnt think it was the cam phaser but it was the only other thing that he could think of. He tried putting in a motorcraft plug in cylinder 7 and it still missed and spark knocked. He also swapped the coil from another cylinder. I told him well take the programmer out and see if that will make a difference. He said he was getting ready to go home and that will be the first thing he does in the morning. He said if it still does the samething he is going to put in all motorcraft plugs and see.

I called Mike which sold me the programmer and asked him if the programmer could be messing it up. He said it shouldnt be and it could be the plugs. Well its weird that it still did it with a new motorcraft plug in that cylinder. Good news though he said he is not charging me anything cause he has not fixed the problem and he cant charge me for something that he didnt fix. The plugs that got put in a month ago were Champion double platinum plugs. I will keep you posted.

 

This sounds just like a problem i had for a while. You can read back on some of my posts over the last couple years. First was a broken plug. Then it was a coil wire. Then it was a second coil wire. It ran great for about a month then the problem was another coil wire. It ran pretty good for another couple weeks, then again, misfire and bad shaking. Only did it when completely warmed up and driven hard. I decided to say g-by to it. I would say it is not internally caused though. Coil, plugs, electrical, etc. Just my 2c. on it since I threw a lot of cash at a similar issue. Good luck!

 

Oh, and I had an Edge programmer and it did it on all 3 programs, and stock and removed.

 

Fuel pump solved it for me for a bit as well.

 

I would also lean toward ignition. It might be in the wiring harness. There should be some codes though. It might not be a plug or coil. A lean condition could cause misfire as well.

 

Well got it back yesterday. I had the mechanic remove my programmer and put it to stock. He said it ran worse which is weird. He said it misfired and spark knocked worse. So he went to the ford dealer bought 8 new motorcraft plugs and installed them. It runs great now. The plugs that were in it were Autolite Double Platinum plugs which the first mechanic said he was told only to use these now cause they wont break off. So far its running great again. He only charged me 160 for the plugs and labor and never charged me for removing the valve cover and fixing the cam phaser. So its nice now cause my engine dont tick as loud now and got it fixed for free lol.

 

I had the same thing 4 years ago on my 4.6 have only fitted genuine plug since then and it is now on 180K and 5.5 years

 

Hey thats awesome man congrats I hope it stays this way for you but look at the long run of it you know that the rest of the engine is in good shape now after looking at everything else.

 

Ya as much I was mad cause he couldnt figure it out I was happy cause knowing that everything else was good.