My 2015 Dodge Charger shuts off while driving- mostly on highways at speeds 50-75mph.
had fuel system flushed and 2 injectors replaced.
fuel relay was getting very hot so it was replaced.
when it shuts off, it says press brake and start. If you try to start it immediately, it sputters and doesn’t start. After 5-10 minutes, it starts up and may not shut off for 2 days or shuts off in 15 minutes.
no codes are present and no check engine light.
Today it shut off 7 times. The longer we let it sit before starting back up, the longer it would make it.
what could this be??

Update: Had the Engine Control Module replaced and it ran for a couple hundred miles and shut off again BUT this time the check engine light came on and it produced a code. We replaced the crank shaft sensor and it has been running fine for 3 months.

It kinda sounds like a fuel delivery issue... maybe the fuel pump is failing/overheating. I'd try spraying something flammable ( like carb or brake cleaner) directly into the throttle body during the non-start condition, If the engine can be made to run this way. I'd follow up with fuel pressure and flow testing. Pressure should be 58 psi ± 5 psi.

I had the same problem with a 5.7 hemi. It ran great but would suddenly shut down. No engine warning lights. The original plugs were changed out with Bosch plugs. It ran extremely well on the plugs but caused the engine to shut down randomly. After contacting Bosch they said at the time they didn't make a plug for that year 5.7 hemi even though the parts store had a listing. After replacing with factory plugs the problem was solved.

Did the shut down start immediately after putting in the Bosch plugs or after a few hundred/or thousand miles?
This charger had the spark plugs changed @ 6,000 miles ago but until 500 miles ago, it ran fine.

The stalling started within 100 miles. It could trigger a light to come on by doing the following, but it will eliminate a venting problem. The gas filler that comes with the car can be propped in the fill hole. Give it a run and see if it stalls out. If it doesn't you've got a vent issue.

Shooting in the dark..... I agree on the fuel system issue "Fuel Pump?" or if you have added anything new wired into any part of the electrical system, look their....

Update: Had the Engine Control Module replaced and it ran for a couple hundred miles and shut off again BUT this time the check engine light came on and it produced a code. We replaced the crank shaft sensor and it has been running fine for a month now.

Glad to hear you found the 2 problems !!!!! How it runs good for a long time for you... Cheers...

Wow, it's super frustrating this kind of breakdown, especially without an engine light or codes… I had a rather similar problem on my old Dodge, and in the end it was the crankshaft position sensor that heated up and cut everything off. It could also be a failed PCM or a mass problem somewhere. The fact that it restarts after cooling really reminds me of an electrical component that is overheating. Also try to have your TIPM module tested, it can cause weird cuts. Good luck, I know how hard it is when the car turns off while driving… Keep us posted if you find the cause!