1994 Ford Astrostar van
The engine when running surges high and low. What could be the prob? The vehicle has been sitting for over a year.
could be a vacuum leak, of course, but the controls that regulate idle speed would no something was wrong...connect your diagnostic tool (about 40 bucks for one of these) and reveal what's goin' down in this town.
After sitting a year, it could be many things. Gaskets and seal are dry. Electrical connections are corroded. Gas is old. Squirrels have been chewing the wires. Chipmunks made nests in the air cleaner. Get it up to temperature, run it on the road, refill the gas tank, step on the gas a few times, replace the filters, etc.