|
I've seen it before on engines including injected '75 Opels.
On carb equipped cars it could be a couple of things
involving timing not retracting fast enough or air not being cut off fast enough.
Weak or broken dist. mechanical advance spring(s)?
Mechanical advance mechanism binding and not completely free to return to
zero right away?
Would that carb have some sort of delay built into it for returning to full idle,
like a anti diesel valve, solenoid or dashpot?
On the '75's, it's probably the Deceleration Valve which is designed to do this for emissions reasons to allow extra air into the cylinders to more completely burn and left over raw gas. I just plug the vacuum line going to it to stop this annoying designed in trait.
|