Hi - I notice this mostly at highway speeds......when I let up on the accelerator I feel a bucking sensation....it's slight but definitely noticable. Once I step back down on the gas I do not feel it anymore. What do you guys think....Thanks for your help.

Hmm, bucking you say? Do you feel something similar when braking or only when you let the gas off and coast?

Only when I let off the gas and coast....I've timing maybe....although the car runs great. Isn't there a "let down valve"....something like that which smooths out deceleration??

Mine did this when I first got it. Hard to say which cured it, but my valves were way off and my timing as too advanced. I also had a leaky vac hose to the dizzy. Fixed all that at once, and it was cured.

I had to go to your profile to find out what car you own but what you are describing is typical of a throttle position sensor that is gunked up... Sensation will usually happen at steady state cruise. Pop the cover off and look at the circuit board. It is sometimes possible to clean it up and still use it.

I would describe this more as surging than bucking but yeah, I think conedodger is on the right track.

If you have SUs try richening them up a half turn and see what that does.