S320 Cdi issues again!!

[m2287]

Having issues with my 2004 s320 CDI online 6 engine. The problem is:

First thing in the morning it takes up to 10 seconds to start and there is quite a bit of white smoke when it does start. It ALWAYS starts first time and it will start immediately on the button until the next morning no matter how many times I use it! (It does need 3 glow plugs so this could be my issue!

Anyway that could be related to my main issue... On hard acceleration, it goes into limp mode and el. Power control EPC visit workshop comes on the dash. On restart it still displays the error message but won't be in limp mode until you hard accelerate again.

I changed the fuel filter yesterday, no difference.
The car had new fuel lines, HP pump, and a recon injector number 3 only 9 months ago due to fuel contamination. It has run fine since then and done around 15k miles.

Did a smooth running test on autologic and it all came up fine on idle but when we tried to do it on WOT, the data would freeze.

The error code coming up is PO256, injection pump B - circuit malfunction (cam/rotor/injector).

Any ideas?

 

[bob6600]

Check the rail pressure, I don't know the correct figure but an Indy should. You seem to have changed most parts but not resolved the problem. Might be worth paying for a STAR session with someone who can interpret the data

 

[m2287]

Check the rail pressure, I don't know the correct figure but an Indy should. You seem to have changed most parts but not resolved the problem. Might be worth paying for a STAR session with someone who can interpret the data

Rail pressure was 69bar I think

 

[m2287]

Rail pressure is meant to be 325 bar... Hummmm

 

[m2287]

Sorry, rail pressure is 742 bar under load and 330 bar on idle which is within spec...

When I clear the code and accelerate hard I can hear a slight knocking noise from the engine above 4K revs, it sounds like when you try and start a diesel using easy start. I believe it's over fuelling on a worn injector, will do a leak off test on Monday under load to find out which one

 

[m2287]

Sorry, rail pressure is 742 bar under load and 330 bar on idle which is within spec...

When I clear the code and accelerate hard I can hear a slight knocking noise from the engine above 4K revs, it sounds like when you try and start a diesel using easy start. I believe it's over fuelling on a worn injector, will do a leak off test on Monday under load to find out which one

I should add that this only happens when under load, when in neutral or park, I can Rev the life into it and I get no warnings or knocks from the engine!

 

[boyt]

Hi.
I had very similar issues with the wrong pump being fitted, the 611 and 612 pump will bolt on and looks the same, but will under perform, check the numbers on the plate on the pump. If unsure send me the details and I can check for you,
A leak of test might not show for poor starting issue. But I would remove and check flow rate and spray pattern of your injectors,

Andy

 

[sprinter316]

Is this a613 or 648 engine? I can test all Bosch injectors and cp1 pumps if needed,

Do you have the chassis number

 

[m2287]

I think it's a 648. I did have an injector that was chuffing for a while so it could be that it's finally given up although it's been fine since I put a new seal on it a couple of months ago. I've ordered a new injector to try that anyway.