Just a few days ago my 99 Expy has gotten moody on when it wants to start. When I turn the key I get one click and then nothing. If I do it a few times it will usually start. I checked the Haynes book which said to jump the ignition connection on the starter relay to the pos. term and it turned over every time. I put some di-electric grease on the ignition bolt and it seemed like it has been working, until I went to leave work today. Took two times before it started. Any suggestions where to start?