Accelerator not responding at times for powerstroke 6.0. . Maybe bad fuel, replaced filters and drained tank. Still seems to be driving bad at times. Runs fine then won't accelerate, then after a bit it runs good again??

What year is the truck?

If the engine is running but just no reaction from the accelerator then you could have a problem with the reference voltage (vref). This engine has three separate vref systems, two are 5v and one is 12v and it's easy to overlook the 12v system. None of the three systems are quick and easy to diagnose. You may already know that there is no mechanical link between the pedal and the engine, it's all electronic. I've been involved with cases with vref causing a similar issue.

As always, without putting my hands on the truck this is just an educated guess.

2 things first check your engin oil,and get your votage check on your alternatior low vots will cause this problem

Your problem is you bought a Ford!!

Sounds like intermittent turbo lag. These trucks have variable geometry turbos and are notorious for having the veins hangup when the components oxidize and rust. If its under the 100,000 mile mark I'd let them deal with it.

Keep us posted.

For what it is worth, you'll have better luck getting this issue figured out at "TheDieselGarage.com"

I heard a grinding noise right after starting