W220 320cdi still starting problems

[leicschris]

Hi all

Not only am I still having starting problems first thing In the morning, it is now giving me problems through out the day now.

Previously I have changed the glow plug relay and the coolant temp sensor.

Last week I took it into Mercland who changed the diesel pipes, fuel filter and split breather pipe and since then it has been worse than before.

Symptoms are that it takes up to 10 mins to start of constant cranking

Sometimes it seems to sound like it has kicked in and started for a second or two before cutting out again.

I'm not sure it's a fueling fault as this morning when it did finally start a bit of white smoke came over the car with a distinct smell of diesel which may be unburnt fuel when cranking.

Star reports and I now have three of them are not showing any faults in the cdi system

Any ideas now guys

Thanks

Chris

 

[BlackC55]

Check the injector leak off and the efficiency of the high pressure pump.

 

[leicschris]

Thanks for the suggestion

How are these checked as the star report does not mention them

I assumed the fuel pump was ok as when running the car runs well. I did ask the mercland mechanic about the fuel pump and he said when they fail they usually leak and that mine wasn't leaking

Thanks

Chris

 

[mersum1es]

There is hp pump test in under the idle test. Never tried myself, not even in simulator mode. Maybe I should bother...

Injector leak test is easy DIY https://www.youtube.com/watch?feature=player_embedded&v=jyuFCjf06-4 (block the removed fuel line)


What is star showing to fuel pressure during start attempts?

 

[bob6600]

Jay's guys are pretty good, Reggie is a knowledgeable mechanic. However, some time is needed to diagnose your fault properly, no fault codes doesn't mean car is ok (looking at yours). Have a word with Jay (he is on here) but better to email him through his site and explain you have had a diag and pipes changed but car is no better and if they can diagnose the fault properly.

 

[dev]

Could it be the cps causing the issue

 

[leicschris]

thanks guys

the 3 star reports have been static basic reports, none have been live reports so i cant tell what the cranking pressure is.

i did think about the crank sensor, but also read about the rail pressure sensor and valve, and also a cam sensor, thats why i'm stuck.

I've also seen posts about ecu faults causing bad starting so its a bit of a minefield.

I have also noticed at times before it starts the cooling fan on the radiator spins at full speed?

thanks

Chris

 

[mersum1es]

Cooling fan indicates low voltage of ECU, but may be due to long cranking.

Live data would be great help to pinpoint in first place is it fuel related or not...

 

[leicschris]

Hi All

I think I have finally solved the starting problem on my w220 s320cdi

I called mercland yesterday to arrange a leak down test as the starting problem was getting worse and was told to bring the car in when i could.

This morning I was about to bring the car in but it refused to start at all, not even after its usual 10 to 15 mins so I had to resort to calling out the AA

The car then started when the AA used easy start but would immediately stall again so I asked him about the CPS and he got his Bosch diagnostic laptop out and the only faults showing was no6 glowplug and the camshaft sensor.

He cleared the faults and tried to start the engine and again the same faults showed. He also got a live reading from the CPS showing it was fine.

I picked up a new camshaft sensor from Euro Car Parts for £22 and fitted it and the car started first time.

Been starting first time on numerous times since, and seems and sound better starting than it ever did.

The AA man reckoned the common rail engine only uses the camshaft sensor for starting and once started uses the CPS for running.

will see how the next few days goes but fingers crossed its now sorted and i can move onto other issues, ie. the ball joints etc,

thanks for all the advice

Chris