Wiring Harness in Grand Caravan

Please help! We have put a lot of money into our van and it has started running rough after we wash it…or it runs in rain…sounds like the wiring harness is acting up again and we can’t afford after the $800 bill we got last time for hours spent on fixing it and within a few months it is back again. Anyone have any idea how we can trace it?

This same thing happened to our '02 Chrysler van shortly after we purchased it. The shop replaced the PCM and some injectors with no help. They finally replaced the engine wire harness to fix the trouble. I inspected the old harness to look for signs of trouble but didn’t find any. I suspect the trouble was due to a connector problem.

If you have any codes show up I would look for clues to the trouble there first. You may be able to use a spray water bottle and spray small areas to see if the trouble will show up then. The ignition area would be a good place to start with.

How old is your van? Please give us year, engine type, anything that will help. Your question is rather vague at this point.

Have the spark plug wires been repalced?

I don’t know exactly what years this pertains to but Chrysler, (in all their wisdom) had the wiring harness connector mounted under the battery box. When a battery leaked the acid dripped on the connector and that resulted in a bad wiring harness.

This sounds like a ignition missfire. Have the igniton wires been checked or replaced?