Ok so I have been chasing around this damn miss on my truck for a month now. Little history on the situation. We put a new( junkyard with 45k) motor in it this summer started it ran like ****. So I bought some new coilpacks from ebay and new NGK plugs ran like a champ for about a week. Recently it has this misfire when it shifts into overdrive or when you lightly accelerate or set the cruise. It missed so bad it's like a buck or a jerk not just a little miss. Drive it with overdrive off runs fine but drinks gas. No check egine light though. Replaced MAF both bank 1 o2 sensors and checked and found no vaccum leaks and the EGR is working fine. So I have heard these motors are very sensitve and do not like anything other than MOTORCRAFT plugs which I picked up today. Now my question is has anyone had NGK or other non CRAFT plugs cause a missfire simmilar to this. If you turn overdrive off or hammer it down it runs fine. I am going to change them Monday just want to get a poll going to see if people think this is gonna work. If not I think i'm gonna torch it or sell it cheap. I'm tired of chasing this mystery missfire. Let me know what you guys think. MOTORCRAFT to the rescue or not

 

Anyone have an opionion??

 

4.6? since you said you bought "coil packs" I'm guessing. Which ones did you buy? Or from what ebay store.. Which NGK plugs?

 

No 5.4 I bought all new COP's I dont remeber what store they have a white gel on the top of them instead of saying motocraft. And the NGK's were the stock equal to motocraft from advanced.

 

Reason I ask, it is a common occurrence to have bad coils new out of the box. Seeing a lot of them lately, mostly from uneek supply (ebay). Your on the right track swapping the NGK's for motorcraft. You said it ran great after the plug and cop change for a week, then like crap. And from what you described, sounds like a classic low grade misfire. More than likely a bad coil. And like I said, it is almost a daily occurrence around here to hear about bad coils right out of the box. Thats why most people buy the 10 pack for the v10 from Global automotive. Plus there have been less bad ones from them.

 

I still have all the motorcraft cop's from the junkyard motor. Maybee I'll start swapping them out. But If I had 1 bad cop wouldnt I get a light? Thats why I was thinking it was plugs and I just had them missing on all differnet cyl's and thats why I wasnt getting a check engine light. I was just told that the modular motors are very picky and only like Motorcraft plugs is why I ask. Thanks for all the help TOYZ you helped me last time I needed it you are a stand up guy!!

 

Negative, matter fact most people chase a bad cop around because it won't throw a CEL. If you can get it to stumble hard enough and get the cel to blink (sometimes), even though it doesnt stay on, it will store a DTC in the KAM which can be read by a scan tool that can read mode 6 data. Since you have a (hopefully good?) set of motorcrafts, wouldn't hurt to swap them out. If they are good... are they the ones you had in originally with the misfire?

I don't think many people have issues with NGK's. I just like to use motorcrafts but as far as I know, people like the denso's and Ngk iridiums. I'm not sure about their standard plugs though.

You said you tested the egr?

 

I use NGK R iridiums.....

 

I think mine were the ngk platinums. Gonna swap to the factory motorcrafts hope it fixes the problem I'm tired of chasing this miss and my truck chugging gas

 

I had this exact same problem and changed the spark plugs (process sux). Anyway, it fixed the studder but not the buck. After changing my tranny fluid it worked like a champ. I only drained the pan and refilled which holds around 5 qts. Change your transfer case fluid also if its 4x4. Sometimes the seal between the transmission and the transfer case goes bad and overfills it. Make sure you use mercon v and motorcraft spark plugs.

 

Does anyone know what the factory Motorcraft plug number is for a 2001 f150 with a 5.4? What should I gap a them at .054? And is the tourque spec 13 ft pounds? Sorry for all the questions I just dont wanna shoot a plug out of the head

 

Just put new fluid in when we did the motor swap because I lost about 4 quarts when we pulled the dipstick. But mine also misses at idle

 

Torque to 28 ftlbs with no anti-sieze.

 

Wow 28 really that seems kinda tight. I have heard use antisieze because the ford manual tells you to use it I have heard not to use it. I dont know what to do. I DO KNOW I dont wanna shoot a plug out of the head!! Anyone know about the plug number and the gap?

 

Any suggestions for getting the #7 plug out? Or easier than removing the fuel rail? Hubby just changed all mine (well except #7). He's diesel mechanic. He used the anti sieze and torqued them beyond 28 ftlbs. Says not to worry, they won't be coming out unless he wants them to. Planning to put on new COP's as soon as we get them, but doesn't seem to be an issue right now.

2002 F150 5.4L Lariat SCrew with 146,xxx miles.
I'm the second owner. Got it in September 2010 and I think this is the first plug change. I believe the manual states gap at .052 -.056. The plugs came pre-gapped at .054