Krunchw

Hello im having major issues with my 03 c240. Ive replaced fuel filter, fuel pump(bosch parts), checked all related fuses and relays and they all checked out fine(under hood and in trunck). There is no fuel pressure to the fuel rails despite the new pump which i hear humming when key is on(no spray of fuel out of the schraeder valve even when cranking).Car will fire up when starting fluid is applied and run smoothly until the starting fluid is comsumed. I also replaced the CPS for good measure since it has previously failed prior to the fuel delivery issues. Will a faulty driver side sending unit prevent fuel delivery to the rails? Is there a fuel pressure sensor that could be faulty? One code read by OBD for secondary air injection, but i dont believe that would keep the car from firing. Please help...

jhk777

Clogged fuel filter?