I'd also test your TPS voltage, regardless of it not throwing a code. http://www.fordfuelinjection.com/?p=30

 

Well swaped out the EVP and still getting stumble and code 34. Will recheck the TPS cause truck was idleing a little high. Someone also suggested the inline fuel pump so I'll check that tomorrow.

 

I don't think the TPS is the problem, but would like to see if you're buying.

 

Sounds a lot like what I just went through. I was getting the 23 code.
It was the TPS- I replaced it (around $40).
Had to take off the throttle body.
While in there, I cleaned everything including the EGR with carb cleaner

Has the truck been sitting for a while?
If so i bet it's the TPS- at least that's how it worked for me...

 

The truck has never sat more than a week or so. I've already replaced the TPS, but going to check it again and adjust idle if I have to cause it was idleing a little high last night.

Only code is 34

 

If the Idle adjust has never been adjusted, I'd leave it alone.

 

I would check the EGR system better. You're not going to fix code 34 by changing the fuel filter.

 

Changed the sparkplugs cause they looked old and covered with soot. Checked EVPand it reads exactly 5000 ohms. Pulled the O2 sensor off and cleaned the soot off of it. Now the truck reads code 11 but the issue is still there. Thinking it might be a clogged cat.

 

Okay took it out for a drive cause I kept getting the CEL. And now I'm getting the code 34 again so back to square one.

A question I have is if the Cat is clogged and creating too much backpressure could it keep the EGR open, and also create the engine to surge and sound like it's backfiring in the intake.

 

Not sure about ERG but it will backfire, & progressively worse. Surge, and eventually, when enough raw gas gets to the Cat.......Boom! When it's really symptomatic, It acts similar to when the timing chain has jumped. After the back pressure condition subsides, it will run normal till the back pressure returns, then symptoms return until a stall(or the Cat goes boom).