Knock on the interstate

[Wraith]

I drive on the interstate alot. One thing I have noticed lately in 4th gear tying to accelerate normally with around 5 psi I get anywhere from 5-20* of knock running 93 pump gas. In 3rd gear with my foot in it I only have 2-3* knock. What are a few things I need to check? Thanks

 

[WFO]

probably an egr problem...

 

[IrvJr]

Check your chip. I had the exact same prob it was my chip.

Scott