Ignition Coil Failure Due to Excessive Spark Plug Gap on Ford F-150

An illuminated Check Engine Light could indicate that one or more of the ignition coils has failed due to excessive spark plug gap. To fix this problem, the ignition coils that have failed, the spark plugs, and all coil boots should be replaced.

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Average mileage: 117,316 (22,000–200,000)
Engines affected: 4.2L V6, 4.6L V8, 5.4L V8, 6 Cylinder, V8
12 model years affected: 1997, 1998, 1999, 2000, more2001, 2002, 2003, 2004, 2005, 2006, 2007, 2009
69 people reported this problem
35 people shared problem details
1997 Ford F-150- 5.4L V8136,000
i was driving and i herd a pop like something hit my hood and then the truck sounded like a motorcycle, i took it to a friend and he said the # 4 plug popped out. so he fixed it for me but a year later i still have problems with misfire on #4 had new boots put in but every six months still misfires
16 people like thisFlag inappropiate
What is happening with these coils going is a few things. First the spark plug could be bad causing the coil to go and secondly the plug wire ends if they do not have di-electric grease packed in both ends, the least bit of moisture is enough to screw it up. These models have been known to have a bad design as far as the coils (in which #5 and #7 are ususally the culprits ) of letting water in the wells where the plug is. I am experiencing it also but have found a guy that knows exactly how to fix the problem. My conversation had just started and he stopped me and said, " Let me guess, this is whats happening " and he was spot on and continued to tell me how he has fixed them.... two weeks before he can get to it though....grrrrrr.
14 people like thisFlag inappropiate
2006 Ford F-150- 5.4L V880,000
A couple years ago I was driving home and all the sudden engine light came on and car started sputtering/ misfiring around 50 miles per hour. Had full tune up done which cost a lot of money, replaced all spark plugs and coils. Since then every few months same issue with 1 coil = #5. Replace spark plug and coil/boot assembly and good for another couple months, pain in the butt. UNHAPPY Truck has been taken care of ... only has 115,000 miles and should not have to deal with this every few months :(
12 people like thisFlag inappropiate
2004 Ford F-150- 5.4L V860,000
If the spark gap is set to Ford's spec.s, what the h... is the gap that will keep the d... coils from blowing. I have experienced failures about every 3 to 6 months for the last couple of years. Going send me right back to Jap trucks.
12 people like thisFlag inappropiate
2004 Ford F-150- 5.4L V896,000
misses when i go to accelerate
12 people like thisFlag inappropiate
2006 Ford F-150- 5.4L V8128,000
engine was missing between 40-50 mph until the check engine light was continuosly lit no codes were revealed. mine was the number 1 cylinder i replaced just the one as 1,000 for all 8 is out of my budget.
11 people like thisFlag inappropiate
2000 Ford F-150- 4.6L V8157,768
Vehicle started skipping intermittently, expecially noticable when I accellerated. I replaced the ignition coil.
10 people like thisFlag inappropiate
2003 Ford F-150- 4.6L V8145,000
Engine cut out during light acceleration. More often on warm weather
8 people like thisFlag inappropiate
Bought used truck with 100K on meter; at about 120K, the engine began eating coils about 1 each year for the last couple of years. First was #4 in the summer, then #6 the following spring, now, #5 in the mid of winter. "Check Engine Light" didn't come on until the miss was very bad.
8 people like thisFlag inappropiate
2005 Ford F-150- 5.4L V8119,062
Engine light came on ran test with scanner found a miss fire code. Found bad coil removed spark plugs all where bad along with one coil. 2 of the spark plugs where stuck in the head and had to be removed coasting extra money. now it runs great.
6 people like thisFlag inappropiate
2009 Ford F-150- 5.4L V859,000
For no apparent reason engine started running rough, I thought I had a flat tire at first. Made it to repair facility auto tech confirmed issue was related to ignition coil failure on number seven cylinder. Cost me 200 bucks to get it fixed. Ford may have put this engine together in Michigan but the parts associated with the problem were made in Mexico. Thanks NAFTA and Ford, i'm spent $40,000 on this truck for quality and that is what I expect.
1 person likes thisFlag inappropiate
2006 Ford F-150- 5.4L V8155,800
Multiple Coil failures...caused Catalytic converter failure. All spark plugs coils have been replaced by the dealer more than once. My truck continues to have coil issues. problem not resolved.
1 person likes thisFlag inappropiate
2002 Ford F-150- 5.4L V848,876
check engine light came on.....ran rough, took to repair shop and had them plug into it to check the codes and sure enough the number four cylinder misfires.
1 person likes thisFlag inappropiate
2003 Ford F-150- 5.4L V8170,000
I had a misfire and took it in, mechanic replaced the ignition coil. Ran fine for another year (but I don't drive much, so only about 4,000 miles) then another coil went out. I had that replaced, then another month and about 2,000 miles later ANOTHER coil went out. By this time, I was tired of paying the mechanics so I did it myself which was pretty cheap, about $75 and 30 minutes. Another 500 miles and another coil is acting up. I'm selling the truck. Perhaps there is something you can do with the spark plug gaps, but I don't know what it is. All I know is my next truck will be from Toyota or Nissan.
2002 Ford F-150- 4.6L V8180,000
Three different coils have failed, at different times over the life of this truck.
2001 Ford F-15069,000
just had to replace one spark plug & coil @ 69,000 miles. Cost $300.
2001 Ford F-150- 5.4L V8190,760
Misfire on cylinders 3 and 8. Possible ignition coil failure. Still trying to evaluate the problem.
2006 Ford F-150- 5.4L V8128,000
Ran codes have two fouled plugs. Plugs are 3&4 oppisite of each other. Truck runs rough when warm and act's up at times when warm going down the road she fine good pick up But when coming to a stop it boags down.
2002 Ford F-150- 4.2L V651,500
misfire on cylinder 3. New coil and spark plugs were installed, problem fixed.
1999 Ford F-150- 5.4L V879,800
#3 spark plug ejected out of engine head
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