The pre filter is accessible without removing the intake. Also, check the delivery valves and check the rubber hoses that go to the fuel lines under the manifold that run to the tank. Also the shutoff valve as well.

__________________
Only diesels in this driveway.
2005 E320 CDI 243k Black/Black
2008 Chevy 3500HD Duramax 340k
2004 Chevy 2500HD Duramax 220k