What do I check?

my 1995 caravan idles rough, and dies when running unless it is in Park. It smells gassy. Have changed plugs and wires. What do I do next?

Do a code scan on it…see what comes up.

Pull the spark plugs and EXAMINE them. They have things to tell you. Then, replace with new spark plugs. Have a clean air filter, of course.

Unfortunately you have a number possibilities here.

Since it dies when running and smells gas, I’m going to suggest that you have a cylinder or two not firing. That would suggest a distributor or coil problem. Buy a spark tester and see.

You could also have a vacuum leak or a leaky injector.

If it were not for the gas smell I’d also suggest the idle control valve and perhaps even want to look at the exhaust gas recirculation valve and port.

You might also want to check the fuel line pressure. A dying pump can starve an engine.

Check for a leaking fuel pressure regulator. If the diaphram in the regulator has developed a leak, gas will be drawn into the engine via the vacuum hose and flood the engine, which will make it smell like gas.

Locate the regulator and remove the vacuum hose. If gas leaks out of this connection, replace the regulator.

Tester