I own a MY87 Subaru GL wagon, 2WD, SPFI, non turbo, 1.8L. Engine misfires once it reaches operating temp, then stalls. Stalls when operating at both highway speed or while idling at a stop light. Once stalled, it will only start again if I "rest" it for about 5 minutes. Problem is getting worse. Used to happen about every 30 miles, then every 10 miles. Now it stalls and won't re start after only 2 miles. Spark plugs, PCV valve, air filter & fuel filter are new. Fuel pump ok. Cleaned distributor cap. None of that helped. Car has about 140,000 miles. Not looking to put much money into it, but it's usually dependable and would spend a little to get it running again. Any suggestions.
try cleaning your throttle
could be
throttle positioning sensor