I have been experiencing an intermittent misfire on my truck. It has only done it once in a while and usually when it is raining, but it has done it once when it is dry outside. I took it to a friend with a scan tool and it said that there is a misfire in #4 cylinder. What is the most likely cause of this? I did try to do a search before posting with no luck. Any help will be appreciated. The truck is a 98.

 

There is a TSB out for a faulty roller on the cam.

That could be it.

But I hear it is not intermittant.

Greg



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Greg
'96 Triumph Thunderbird
'99 Ford F150 XLT SC 5.4
'00 Lincoln LS8
Wichita

 

there has also been problems with the top radiator hose leaking on the coil packs and misfireing the plugs

 

back in the good ol days when you used to open the hood and actually see an engine, that symtom almost always was a distributor cap problem

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96 F150 XL,special
Air/PS/PB/AM-FM-Cass/
Light Package/300 I6/
5 SP Man/...
Nothing fancy just my little baby

 

How many miles? Could be time to change them.
have you pulled the #4 plug and cleaned it? I just did a sparkplug change I used the Motorcraft plugs, I like them better than Bosh.

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1998 F150 Triton 5.4L
K&N Air Filter

 

Nacho, do you have any tips on getting to all the plugs. Those things are buried!

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97' F150 XLT 4x4
5.4L V8
3.55 gears
Bright red
Off-road pkg.
6-disc cd
Torsion bars adjusted for lift.
Custom rear lift-blocks.
LT275 70 17 Goodyear Wrangler GSA tires.
Edelbrock IAS shocks.