I have a 2001 supercrew 5.4 when Im driving on highway it feels likes its bogging intermittingly likes its shifting slow it doesnt do it all the time almost like a miss. Any ideas? Thanks jrds

 

Any Check engine light on or any other symptoms?

 

my 03 sounds like same problem. Studders (misses) only on light accel usually only once in overdrive. Like trying to accel up a slight hill, put foot into it dropping trans to 3 or 2nd stops it. Doesn't do it while on the flat and steady speed. I was told the coils are prob to blame. Summit has a set of 8 for 270. Dealer put one on my truck last year, was 100 for one!!
Buddys 97 4.6 did same, he changed all the plug wires and is fine now.
My truck does it less when it is really cold out (Below freezing -15c)...GRRR

 

Wish I read this post before dropping my truck off at the dealer today to have 1 coil replaced. I am going to order a set from Summit for preventive maintenance as I'm sure more will go bad. This is my first bad coil in 161k miles.

 

The number 8 coil was starting to short but the check engine light never came on I replaced , Its been raining alot here in texas and I probaly shorted one when it got splashed.

 

Just an update. Ordered coils from Summit, (accel brand thats all they had in stock) Replaced 6 of 8 ( had to go buy knuckle for socket to get the last 2 out). On the way to get knuckle, all problems solved!! Will change last 2 out this weekend. Also have noticed a slight improvement in gas mileage. About 50kms more per tank. OH YA. Shipped to Canada 2 weeks just under $400 AKA 1/2 of the dealer.