4.0 help "bucking"

[kw358]

I was driving about 35 mph and truck started (best way to describe) bucking. I accelerated and it became worse. I took my foot of the throttle and it stopped. Ran fine after that. A few days later it happened again. Now every once in a while it feels like it wants to do it again. It starts,idles and accelerates. Any ideas?

 

[kunar]

Next time it happens disconnect your tps and see if that makes any change.

 

[kw358]

Thanks Kunar. I'll try it.

 

[kw358]

Replaced fuel filter,1 bottle of heat. It's running great! I'm blaming ethanol.