hi gang, she started shuttering on me today on my way to work then got to bucking real bad on the 5 mile drive home.
worse under load (like pulling a incline)
I suspect a misfire on one of the Cyl.'s

the CEL did come on. getting a code reader tomorrow.
what plug's and boots do I need ?
I figer I will start there , if that don't work then I will move to the affected cyl's coil. if that don't work I will be back on here begging for answers...LOL

ALSO is 13 MPG on the low side of average??? I know they don't get great mpg ,but really only 13?? she has 145,000 .
I was kinda hoping for 17 or so

Thanks in advance
Steve

 

I would use Motorcraft plugs .

 

Double Platinum's for sure on the plugs. What engine do you have? My 98 f250LD has the 5.4 and I seem to average about 13 during the work week which is a combination city/hwy drive. If I take a long trip I usually get about 16, but never quite hit 17.

 

it is a 5.4
I am sure it is over due for a tune up.

 

At 145k miles, if you have not put in plugs, it is time... but your CEL is the COP 90% of the time.

 

Thanks. I bought it with 142.000 on it only had it a few months.
but I am sure your right it probably has never had new plugs.
I really like the truck , my favorite thus far. I think i actually like it more than the f250 cc I had.

 

I changed the plug boot and coil on cyl 4.
now it says misfire on cyl 3.

 

changed all the boots and plugs.
I can tell a huge difference now.
thanks gang.

 

Glad you got it fixed ! Thanks for posting it .