my 2014 chevy 4500 express is hard to start once running it does fine , starts right up . If I let it sit for a day or more it does not want to start , after several tries and 5 minutes it will start most of the time. Runs fine once started no problems. no check engine lights.

 

We need to know what motor you have. Mileage would be helpful as well.

 

Sounds like fuel pump is losing it's prime. Spray some fuel or starting fluid into throttle body and if it starts this is the problem.

 

I believe I found the problem the fuel pump relay was rusty I replaced it. I am going to let it sit for a few days then see if it starts , I hope this is the problem lot easier than fuel pump. Thanks

 

Welcome to the Chevy Forums.

After 5 years or so, I begin to suspect balky primary cables. Start by replacing your negative battery cable, and your engine to firewall ground-strap. Corrosion and verdigris create a very hard start
condition. Especially in humid climates.

 

I found my problem it was a bad pump relay, changed with a new one starts fine every time thanks