van has 116000 miles, oil changed ever 3000 miles ,i’m the third owner, my mechanic has changed plugs, wires, distrubutor cap,and the inners, check for vacuum leaks and have found none. It has a 302 fuel injected engine.
Dont know about your van, but my 87 Ranger is not equipped with a check engine light.
So anytime my Ranger is not running as it should my first step is to hookup my code scanner & see if any trouble codes are present.
If this has been done on yours, post the codes here.
You can buy a scanner for 30 bucks and pull the codes yourself in a couple of minutes or have your mechanic do it.
If you get an 11 code “system pass”, put a vacuum gauge on it & see if that gives you any clues.
with a misfire (“skip”), fuel into the engine and spark are always the first suspects. I like the adjustable-gap spark testers ($6). The clamp on it assures a good ground. Connect the spark tester, with the wheel chocked, and the brake set, run the engine at the rpm that the “skip” occurs. Check the spark from each spark plug. Next, run the engine. Spray a bit of Starter Spray into the intake tube (through a vacuum hose would be fine). If the engine runs smoother, a fuel injector is defective. The signal (from the engine computer) to the fuel injectors can be checked with 'noid lights plugged into the fuel injector wiring connector. If if it soesn’t flash, or not steadily, the signal isn’t getting there. Troubleshoot. Whichever (spark, or fuel) is the problem, that’s where your troubleshooting begins. Two gentlemen come to mind: Mr. Haynes, and Mr. Chilton as a big help in the troubleshooting.