CDI Intermittent hard starting
Thread Starter
Junior Member
Joined: Jun 2012
Posts: 17
Likes: 0
From: Torrance, CA
2005 e320 CDI, 2010 ml350 bluetec
CDI Intermittent hard starting
This issue has started to crop up more, basically, most of the time the car starts just fine. Occasionally, the car will just crank and not start. It takes many tries, then the car starts, and drives fine. This has happened both hot and cold, but seems more likely to happen if its warm. I am in southern california, so its never really that cold. One time it threw a crank sensor fault, so I replaced the crank sensor, but this still happens intermittently. I've looked for the "black death" or other leaks, and I'm not seeing anything around the injectors or fuel system. I really don't want to change the fuel pump prophylactically, since the part alone is $1200, although I do have 245k on the car...
I have heard of oring issues causing pressure not to hold, but I haven't heard of which to look at. Is there a residual pressure check valve, that could be letting air or something in?
I have heard of oring issues causing pressure not to hold, but I haven't heard of which to look at. Is there a residual pressure check valve, that could be letting air or something in?
Super Member
Joined: Apr 2007
Posts: 633
Likes: 48
From: USA
2006 E320 CDI
This issue has started to crop up more, basically, most of the time the car starts just fine. Occasionally, the car will just crank and not start. It takes many tries, then the car starts, and drives fine. This has happened both hot and cold, but seems more likely to happen if its warm. I am in southern california, so its never really that cold. One time it threw a crank sensor fault, so I replaced the crank sensor, but this still happens intermittently. I've looked for the "black death" or other leaks, and I'm not seeing anything around the injectors or fuel system. I really don't want to change the fuel pump prophylactically, since the part alone is $1200, although I do have 245k on the car...
I have heard of oring issues causing pressure not to hold, but I haven't heard of which to look at. Is there a residual pressure check valve, that could be letting air or something in?
I have heard of oring issues causing pressure not to hold, but I haven't heard of which to look at. Is there a residual pressure check valve, that could be letting air or something in?
Super Member
Joined: Apr 2007
Posts: 633
Likes: 48
From: USA
2006 E320 CDI
