Hello Everyone! OK, I have had a problem now for many years and am very frustrated about it. I have a 94 Z28 6-speed with a relatively stock LT1 (including good ol' Opti-Spark). Here's the problem: at light throttle (between 1500 and
2000rpm, all gears), the engine runs rough and almost seems to have a miss. I can feel the car kind of "surging" and it is really annoying. If the normal feel of a smooth running engine were described as simply "mmmmmmmmmmm", my engine would feel like this: "mmm-da-mmm-da-mmm-da-mmm-da-da-mmm". To hide the problem, I end up hitting the gas a little harder, but then it slowly -- and obviously -- accelerates beyond the speed I would like to be at and then have to slow down. I constantly repeat this pattern. My alternative is to pick a lower gear and just get the rpm's up a little higher. In trying to fix the problem, I just had opti-spank replaced (3rd time). Could a vacuum leak be causing the roughness at certain rpm's? Can the fuel pump do this (and how)? The only upgrades I have are a borla cat-back and K&N air filter, and I only have 65K miles on the car.Thanks Everyone! Steve- snipped-for-privacy@comcast.net