I can only describe it as a deceleration miss.
It usually happens when the car has been driven a while. Almost always in the summer months. Doesn’t happen all the time.
Car starts fine - has power. I’ll be cruising along on the highway, then if I very slightly lift off the gas pedal I get either one or a few misses. They appear to be a miss or a little shudder. Then it goes away.
IF the engine were misfiring the check engine light should come on. Has the light ever come on?
Could this be something in the transmission or drive train, perhaps, and not the engine?
Knowing the year, type of car, mileage, CEL on, etc. might help, but offhand this could be one of those oddball ignition misses caused by a corroded or scaled over terminal on a coil wire.
While everyone else is speculating on problems with the ignition system or even the transmission, I’m thinking along the lines of a weak EGR. Perhaps the transducer or solenoid doesn’t repond properly under the conditions you described. Unfortunately I don’t know how you would check this out.
The car is a 2000 Hyundai Accent, 5 speed manual, 46k miles.
Could dirty fuel injector(s) cause this?
-tr