Engine/Transmission (1998.5 - 2002) VP??? Help!

[DSeamans]

My truck started Bucking severely. I notice it some in fifth gear and in sixth its terrible. It only does it from 1600 - 1700rpm and when accelerating slightly, as in holding speed up a hill. If I floor it, as soon as I pass 1700 it smoothes right out. I replaced the lp and no change in the studdering and bucking. It does pull better in 3rd - 5th gear. I turned off the comp and it still does it though not quite as severely. It hasnt thrown any codes. I'm supposed to haul a 6000# trailer 500 miles for work next Monday so I need to fix it quick. This is my second lp and original VP has 160,000 miles. Is the VP dying or is there something else to look at.

 

[mhenon]

Have you checked/replaced your fuel filter?

Mike

 

[DSeamans]

Yes, I changed it with the lp. It had maybe 5000miles on it.

 

[DSeamans]

I bought a code reader and no codes at all there either. With the comp box off its hard to duplicate as it wont hold the same speed on the hills. Could the box be causing it or just amplify whatever is wrong?

 

[SnoKing]

I bought a code reader and no codes at all there either. With the comp box off its hard to duplicate as it wont hold the same speed on the hills. Could the box be causing it or just amplify whatever is wrong?

Do you have the Comp grounded to the drivers side battery neg lead. If you have the ground on the engine, move it to the battery. SNOKING

 

[DSeamans]

I don't remember where tis grounded. Its been in for 3 or 4 years.