sprinter 2003 313cdi 903 wont start

[phil049]

hi have strange one:-
bump starts no problem wont start on key even when hot ,battery starter no problem engine turns over no problem,glow plugs good,fuel rail regulator seals look ok not replace though.smells out exhaust while cranking but not lots of smoke any ideas what to do next please

cheers phil

[steel-jaw-sasha]

injector leak back test next job, you will find one or more leaking back too much, stopping the fuel pressure building up.

[sparkyshep]

as above injectors need leakback test