[90pioneer]

My father has a 2019 Wrangler. Manual trans, 98k miles. After it sits for a bit, sometimes it will take 10-15 seconds of cranking for the engine to fire up. No check engine light. Is there a fuel line check valve on these newer Wranglers? Any idea what the issue may be?

 

[Sgt_USMC]

Sounds like the fuel pump needing to prime the lines. IIRC there is a pressure regulator somewhere in either the engine bay or the pump itself.

 

[Wolfslash16]

When you go to start it, flip the key to the "run" position. Let it sit there for 4-5 seconds without starting the engine. Turn it back off, and repeat that a few times. Doing that will make the fuel pump prime and pressurize the fuel lines. If you do that and it still takes 10+ seconds to start, you can very likely rule out the fuel pump.

I would get a scan tool that can read/watch live data, and take a look at the crankshaft potion sensor. If the computer doesn't know where the crank is at from a faulty or spotty sensor, it will just turn over the engine until it sees the crankshaft position so it knows when to time fuel/spark.

Lastly, check the MAP sensor on the intake. If it's going bad or has a loose connection, the computer won't know how to time the fuel and it can cause a starting delay/issue.

 

[Tweak]

Sounds like the fuel pump needing to prime the lines. IIRC there is a pressure regulator somewhere in either the engine bay or the pump itself.

Yep, it's inside the tank and is integral to the fuel sending unit.