1998 4.6 liter misfire #5 cylinder
03-04-2009, 03:20 PM
#11
Senior Member
Join Date: Feb 2009
Posts: 103
Likes: 0
Received 0 Likes
on
0 Posts
update. changed out the other coil pack. cleaned m.a.f. sensor, cleaned i.a.c., cleaned as much of the t.b. as i could without removing it so the egr ports did not get checked or cleaned. checked pcv valve line. found rubber connector on it that was cracked and appeared almost completely collapsed inward. replaced the rubber connector. i took out the spark plug on the #5 cylinder since that was the location of the misfires. the plug was clean. i checked the gap on it. it was not set at .054. it was more like .43 or so. i didn't check any other plug gaps. truck idles great in park or neutral. the hesitation between 40-55 mph range is gone. still have the problem with the engine shudder and miss while sitting at idle with it in gear and foot on the brake. the tack shows around 500 with it in gear at idle. moves up to around 700/750 when i put it in neutral with no miss or shudder. anyone have any suggestions? could it be plug wires. they have about 10,000 on them, but ive heard that they can go bad. its driving me crazy. any advice would be appreciated.
It misses at idle and when ever else it feels like it "30-50MPH". I replaced the injectors the plugs and the coil packs and used dielectric grease.. Next thing I will replace is the truck!
2000 F150 4.6L 98,000 Miles
The design of this ignition system is Junk
03-05-2009, 05:24 PM
#12
Junior Member
Thread Starter
Join Date: Dec 2008
Location: florida
Posts: 8
Likes: 0
Received 0 Likes
on
0 Posts
latest update. i'm hoping it's finally fixed. for now that is. i had the hood up and the engine running. i kept hearing a "ticking" sound. i had heard the sound before. i even asked a mechanic and he told me it was just a fuel injector making the sound. yesterday, i finally saw an electrical arc coming from the #5 spark plug wire. i had looked before, but never was able to see it. the wires were motorcrafts with about 13000 miles on them. i thought they were okay. i replaced them today with new motorcraft wires. no more "ticking". no more arcing. no more misfiring or hesitations. none at idle and none at any range. one spark plug wire, that had low miles on it, caused all the headaches. live and learn, i guess.