High RPM "surges"

[ByUBlue]

My truck is doing something strange at high RPMs in 3rd and 4th at WOT.

 

When I romp on it, and the tach gets to about 4100, (that's high for these trucks) it kinda hesitates and then surges for a half second before it shifts at 42 to 4400. It's like my engine is smothered for a fraction of a second then breaks free or something.

 

I thought that it could be my cat clogged, since it has not been changed since new and has be emitting some strange smells...

 

I want to make sure this is not something major which ignoring could prove fatal to my engine.

 

Any help would be appreciated.

[americanmuscleman]

Things I'd check first:

 

1) fuel filter

2) plugs and wires

3) distributor cap and rotor

[ByUBlue]

1.) Fuel filter...possible, I'll swap to make sure, but why would it only bog in the exact same place every time?

 

2.) Plug Wires and Plugs...brand new platinum plugs and 8 dual path silicon wires...not that

 

3.) Cap and rotor...again, why would the problem only show at high RPMs in a specific place?

 

Not doubting the advice I asked for...just asking...

[SilveradoWV]

My dad has a '91 K1500 350 auto, and I have seen the distributor cap and rotor do weird stuff. Plus it very inexpensive for a good cap, I'd start there first!