Won't Start?? Plz Help
 

Newbe here hope someone can help..I have a 2016 RHD wrangler I work for the post office. When I come back off my 4 hr route. I get back in it to go home and my jeep won't start. It turns over and makes all the sounds it's supposed to make but it won't start. Have hooked it up to a diagnostic machine and nothing comes up. Everything is good. Only codes comes up is catless efficient code and steering box. Mechanic said he left it running for hours and it always started up for him. Please help thank you..

There's always going back to basics... you did not mention so we have ask.... did you pull a spark plug and see if it has spark when engine is turned over ? are you sure you are getting fuel? is fuel pump working? do you have fuel pressure on the injector rail? so you had it on a diagnostic machine and the mechanic who was working on it had no ideas?