i own a 2000 ford f-150 v6 5spd with 105,000 miles on it. when i'm accelerating or going uphill the engine seems to skip. it doesn't do it all the time. i changed the spark plugs and wires in it. it seemed to fix it for about 2 weeks then it started doing it again. i took those plugs and wires out and bought some more plugs and motorcraft wires and it seemed to fix it for about 2 weeks also. i have no "service engine light" or anything. my cousin has a 1998 f-150 v6 5spd and his does the exact same thing. has anyone had this problem with their 4.2? if so, how did you fix it? thanks for the info.
-matt

 

Does it by chance do it at a certain RPM, like 2800 or so. If so, then it is probably when IMRC switches from the short runners to the long runners (or vice verse). Mine does it too.

 

it doesn't do it a certain rpm. it seems to do it at any rpm.

 

If replacing the wires and plugs fixed it for a short while it might be worth checking the coil pack. If its weak it could make it seem like the wires or plugs.

 

i was thinking about that- i just wanted to see what other people thought about the problem- thanks

 

I've been having problems with hesitation for about a year now and have changed all the obvious stuff with no improvement. I went ahead and changed my coil pack, which tested bad according to Haynes specs. It didn't help either.
I've had a dealer do a WDS scan and apparently I'm nuts. My truck is running fine.

Good luck,
Rich

 

yeah- i haven't taken my truck into the dealer yet. i don't plan on it. we took our sport trac in to check something out on it and they charged $88 an hour and found nothing! hopefully someone out there knows the common denominator out there....

 

I have had the same problem with my 2000 4.2 and i was wondering if anybody thinks it could be because of the cats restrictions. My truck has 4 cats stock and to me that could be holding it up.

 

did you try cleaning your maf/tb and iac? pull your rear two plugs again and check the condition see if they have deposits built up? motorcraft plugs make my 3.8 mustang run like crapola, try autolites if you have to replace. you might want to also pull your o2 sensors to check the condition, might be able to clean them by burning off the carbon with a torch, replace your pcv and fuel filters if not already done. good luck

 

i put a new fuel filter on it and it didn't seem to help. when i bought the truck the first thing i did is replace the spark plugs and they are autolites(it had the problem when i bought it).it seems like it is some sort of sensor or something that is causing my problem because it really doesn't skip- it misses, kinda like the engine dies for a second, so i don't think it has to do with the plugs, wires, etc. i will check the things you suggested 99mustang232- thanks for the info
-matt

 

also start your car in the dark, have someone gas it alittle and make sure you don't see and spark plug arc'ing. and maybe check the tps

 

Are you sure its a spark problem? You might want to check the injectors. They might not be getting proper voltage or they could be clogged.

 

how could you check the voltage to the injectors, or atleast make sure the connection is good

 

If you have a obd scanner, depending on the type, it can tell you the voltage going to the injectors and other sensors and acturators.

 

this sounds like a problem I had with my ranger, as well as two other trucks that belonged to some friends. we found that our problems were all the same, and easy to fix. while you're under the hood checking all these other possibilities posted, check the wires in and out of the fusebox under the hood. when the three of us had this problem, the negative wire from the box to the battery was loose. it would cause the trucks to miss pretty bad.