Hard Starting 2003 common rail Cummins ???
 

I have a 2003 Dodge with a 5.9 Cummins 223k miles It has recently become hard to start 20-30 seconds of cranking ! But when it starts it runs just fine. Just don't shut it off-or it will continue to have starting issues. Everything I read on line says 1 or more bad injectors. Are there any other possibilitys ,such as cam or crank sensor or maybe rail pressure sensor ? Any help would be appreciated. Thanks Greg:confused:

Re: Hard Starting 2003 common rail Cummins ???
 

Try taking the line off of the relief valve and cranking it. During cranking NO fuel should bubble out. If it does bubble out it means the valve is not sealing properly and that causes it to not build pressure fast enough to start. If you have a gauge you can check it that way too but most guys dont that is why I suggest what I wrote above.. Should build to 6K pretty quick it needs 4k start.

Re: Hard Starting 2003 common rail Cummins ???
 

I second whats stated above. Have seen many that the pressure relief on end of rail will get hung open a fraction by foreign material, usually shortly after a fuel system repair.

Re: Hard Starting 2003 common rail Cummins ???
 

A big reason why these common rail systems need new injectors and sometimes the pressure relief valve is that Bosch wanted 4 micron or better fuel filtration, but such filters weren't readily available until a couple years ago. The Rams came with 10 micron filtration, and later 7 micron was made available. Commercial diesel fuel in this country often has up to 15 micron particulates.