Sometimes my truck won’t start

Hi all. Sometimes my truck wont start. I turn the key and absolutely nothing happens. No cranking, no clicking, nothing. I’ve changed the starter, key switch and the relay on the firewall. Does anyone think it might be my fuse? If I let it sit for a while, sometimes a long while, it starts. Am I missing something else? Maybe the breaker on the inside of the rail above the starter? I can’t always get a pull or push. Anybody ever experience this?

 

In regards to the fuse, It doesn’t pop out so I’m not sure its bad

 

Peterbilt 379 2003 C15 6NZ

 

Hi guys. This has happened before a few times in the past, but I would turn the key off and on and it would start. Lately its been happening more often. When it finally starts, it will start for about a week then it will happen again. I changed the starter about a week ago and cleaned the posts and put dielectric grease on them. I’m going thru process of elimination. I will check out the clutch suggestion and see what happens. I usually press the clutch down when I start

 

Thank you very much for the comeback everybody

 

Hi Goody. I believe everything works as it should when I turn the key on. My radio comes on my teltek switches light up and the teltek clock is accurate, and any gauges that stay showing temperatures go to 0 when I turn the key on. It’s like a dead spot. What I’m trying to figure out is why it starts after I leave it alone for a while