W211 e 320 estate turns over for ages before starting.

[ramsay2000]

My E320 CDI estate turns over for ages before starting. Usually from a cold start in the morning it will start first time but if it's hot and I make regular stops it can take two or three times trying to start it before it starts and on one occasion it used up the whole battery and wouldn't even start I have recently changed the glow plugs but does anyone have any ideas what this could be?

 

[MCFastybloke]

Air in fuel system

 

[bob6600]

I would also guess at air in the fuel system. Possible failed O-rings or brittle lines.

 

[ramsay2000]

Thanks mechanic planning a pressure test so hopefully get to the bottom of it.

 

[DrNick]

In my experience, air leaking into fuel lines manifests itself by not starting in the morning, but being ok for the rest of the day. This is the opposite of what you've got. Not starting when hot looks to me like a position sensor failing. Cam or crank if fitted. Don't know exactly for this engine.

 

[ramsay2000]

In my experience, air leaking into fuel lines manifests itself by not starting in the morning, but being ok for the rest of the day. This is the opposite of what you've got. Not starting when hot looks to me like a position sensor failing. Cam or crank if fitted. Don't know exactly for this engine.

Thanks Doc! Will pass on thoughts to mechanic. Hopefully get it sorted one way or another!

 

[Major774]

If it is temperature related, it is pointing towards a failing crank position sensor.

 

[mersum1es]

No o-ring problems in W211 (OM64X engines). Low pressure lines are primed and leak shows as a leak. But yes, low rail pressure is probably causing it, usually leaky worn injector, rarely lp or hp pump. Or then cam/crankshaft sensor. Both can be diagnosed by live data reading.

 

[ramsay2000]

No o-ring problems in W211 (OM64X engines). Low pressure lines are primed and leak shows as a leak. But yes, low rail pressure is probably causing it, usually leaky worn injector, rarely lp or hp pump. Or then cam/crankshaft sensor. Both can be diagnosed by live data reading.

Car has done 200000 miles. Injector seals recently renewed as were leaking but all but one injector are the originals I believe.

 

[bob6600]

Looks like I mis-read the original post. As said, hot start problems can be the CPS which do fail.

 

[mersum1es]

Car has done 200000 miles. Injector seals recently renewed as were leaking but all but one injector are the originals I believe.

Totally different thing. I am talking about injector fuel (tank line) leak, as we tak about rail pressure... that test can be done without diagnostic devices but most likely either angle sensors, l ike now said many times.

 

[ramsay2000]

Totally different thing. I am talking about injector fuel (tank line) leak, as we tak about rail pressure... that test can be done without diagnostic devices but most likely either angle sensors, l ike now said many times.

One of the injectors leaking heavily so have decided to replace that as well as crankshaft position sensor.

Will keep you posted

 

[ramsay2000]

So replaced the injector and issue is fixed.

Thanks guys