Vacuum advanced distributor questions

[baker]

SO...I have a 89 auto with a vacuum advanced distributor ive been trying to get going for what seems like ever. I've replaced nearly everything on this car, twice, and it still runs crappy. When you start the car, everything is fine. Idle is good, no stuttering, no shaking, nothing. When you put the car in drive, it nearly dies.

Sometimes tho, the car runs perfect and there is no issues. It seems that if you stab the gas it goes out of time just a hair and then runs progressively worse until it starts stuttering and breaking up under throttle. Could it by chance be something with this vacuum advanced dumb distributor design? Or am i overlooking something else? Oh, transmission was just serviced 2 days ago.

[WmWatt]

I would try pulling the vaccum hose and plugging it to see if there's any change. When I want to look at engine vacuum I pull the top hose off the vacuum advance. The engine starts to die. When I plug the vacuum guage into the hose the engine picks up again.
Also, when checking the timing with a timing light you pull and plug that hose.

[FestYboy]

it's not your dizzy, your '89 is EFI and it's a sticking Idle Air control valve (driver side of the intake plenum). remove unit and soak in MMO.

[Laurel]

It seems my '89 MAY be having the same issue, what is MMO??

[drddan]

Marvel Mystery Oil

[FestYboy]

^ concerning the OP, a careful exam of the Ignition system (coil included) is required as well. the coil can and will break down over time and engine load can show this in it's initial failure.