It is the solenoid. The worn contacts are very common and cause the intermittent no-crank. That symptom will continue to get worse.
This happened to my Caravan a few years ago. Fortunately I was still at school when I heard the starter running. Had to turn off the ignition, then pull off a battery cable. Be careful; sparks can cause vented hydrogen from the battery to explode.
Here's what I did for a temporary fix. Pull the three screws off the solenoid cover, remove the cover, then pry out the spring-loaded plunger. Mine was really stuck in the recesses of the worn contacts. Had to pry it with a screwdriver. To prevent it from sticking again, I ground off a very little bit of the outside circumference of the contact disc on the plunger. Months later when we were in Electrical class, I had my students replace the solenoid contacts. Every student was required to disassemble one of these Nippendenso starters because this is such a common problem. For speed and reliability, I expect them to replace the entire starter in the future for their customers, but for my friends, I've replaced just the contacts many times.
I used to always replace the plunger too but lately I had just as good of results with just replacing the two contacts. There are three versions of the plunger. Two for Chryslers that you can buy from your local rebuilder, and a much longer one for Toyotas that must come from the dealer. There are also three versions of the "starter" contact. I don't know how to tell which plunger and which starter contact you have except to take it apart and look. The "battery" contact is the same in all the solenoids. This starter is used on Hondas too and possibly other car brands.
Monday, January 18th, 2010 AT 6:36 AM