Rumble sounds like miss fire

[sschefer]

Vehicle: 08, F350 SD 4x4 6.4l
Mods: K&N 57 series intake/filter
Mileage: 29000

Symptom: Engine feels and sounds like it looses fuel between shifts during semi hard accelleration. It has also done this a couple of times when it's not shifting.

When did it start: I've only had the truck for a month, after 3 weeks I changed the intake to the K&N. This is when I started noticing it. I'm hesitant to blame the K&N because the stock filter system was probably masking it. This is a California truck and the K&N is the 57 series that is CARB approved.

Any ideas.

[sschefer]

Finally threw a code.. EGR and I lost about 12oz of coolant. I'll pull the K&N off it, put it back to stock and take it to the dealer. I shouldn't have to put it back to stock but why risk it.