92-GC w/3.3 v6--after 2 months sitting, started fine,, then,,,

[3DRCpilot]

First time poster here. From the read it looks a nice group. I have searched for the problem and found many threads. If I had the time and a comfortable place to work on the my van I’d try the all the suggestions and solve this issue. But I don’t. The van is parked in a narrow, dusty, very hot garage. I’m not able to tow it up and outside. So I’m going to have to go with the odds on this one in order to keep my time in the hole to a minimum.

The van has always started fine and ran well except for the once a trip stall at parking lot speeds. (feels like it goes into OD and doesn’t come out- that’s another thread of course).
The only other thing I can think of is a stumble every two minutes or so at idle, but it was small and always caught itself, jumped the rpm’s 200 or so then settled back down to normal, at 500 or so.

The gas is five months old with stabilizer and injector cleaner added, the fuel filter only has a few tanks through it, the O2 sensor is new, the battery was just replaced (love those Optimas), and the code comes out 355. But I think it 12 or 21, 55 because the battery was just done. Fuel pump runs at key ‘on’.

It had been a couple months so I went out and fired it up. Started right off first shot. I let it idle to warm and in about 20 seconds it stumble and died. Hit it again, started fine, ran for 10 seconds then died. 5 seconds the next time, but this time I used a little throttle. It started missing and backfiring, A couple more tries later I got out of the hole and logged into the forum.

From what I’ve read there’s a few areas to look. With the info I have given which is the most likely. Feel free to add any by all means

EGR
AIS pretty sure that’s the term (idle motor thingy)
Cap and rotor
Vacuum leak- I didn’t hear one BTW

Thanks,

John

Oh yea, what the best manual on this year? Is it me or is 92 a between stlye for certain things. Please forgiven me on these Mopars. I'm an old school Oldsmobile hot-rod. Yep,, 2 1/2 tons of sleeper that can pass almost anything but a gas station.

[Bernard Feltzer]

also check the crank sensor.