PLEASE HELP ASAP, my ONLY transportation.
I Love My 1999 F150 , work on a horse farm and I Need her everyday, she’s been well cared for over 300k miles, actually my 1st problem … she stutters out during idle and “stutter” starts again if driving up hill . It doesn’t cut off up hill but will continue to “stutter” for the rest of my drive, eventually it stops. It all starts over again every time I start again and drive it.
Originally research found several matched answers… I need to replace an Air control part , I made mechanic appointment BUT next day (3 days ago) After I filled up with a cheaper gas , That’s when the up hill “stutter” started. I’m suspicious of the gas but did already have 1 issue going on, now 2 issues seem to be related. My last vehicle cost me $$$thousands in repeated repairs. I’m praying the F150 will be a simple little money repair that Maybe I Can Do….Any ideas of What to do next ?

 

Have you had the truck since new?
Sounds like a fuel problem?
When is the last time you changed the filter?
Take a fuel pressure reading?

 

Need to check it for codes to at least have somewhat of a starting point.

 

Be nice to know which engine is under the hood, but my first thought is to pull the spark plugs and see what they tell you.

I did plugs on my 4.2 some months back and they were really oil caked and the engine was stumbling pretty badly. But, no CEL shining at me for that issue.

 

If you suspect a fuel problem, add some octane booster and see if it makes any difference.

 

The symptoms you're describing remind me of a stuttering problem I had on an old Plymouth many years ago. The car would start okay but as soon as I started to drive it would buck. Turned out it was a plugged up fuel filter. That's a pretty simple and inexpensive job. As Big Ed 1 has alluded to, unless you know for a fact that your fuel filter was recently replaced, I'd start there.