Hello all.

I'd like to request some advice, please. We have a Merc W204 (Diesel, MERCEDES-BENZ C 220 SE STARTSTOP BLUEEFFICIENCY CDI).

The car stopped running about 12 months ago, and was left sitting by a family member. Apparently, about 6 months prior the car stopped at one point, as it ran out of fuel (but the fuel gauge said it was about 50% full).



I have been asked to support getting it back on the road for sale.



We have charged the battery. The car now cranks but does not start.



I have run a code scan with a Top Don Code Scanner. The following issues come up:
ECM - Engine Control Module(CDI) 2 problems exist

1.P008700 The fuel pressure in the system is too low.

2.P246397 The soot content of the diesel or gasoline, particulate filter is not OK.The system function is restricted. (400%).

The following systems are OK:

1.FSCU - Control Unit'Fuel pump'(N118)

2.ESP - Electronic Stability program(N30/4)

3.EZS - Electronic Ignition lock(N73)

4.SCM - Steering Column Module

5.RevETR_LF - Left Front Reversible Emergency Tensioning Retractor

6.RevETR_RF - Right Front Reversible Emergency Tensioning Retractor

7.Driver-side SAM - Front Signal Acquisition And Actuation Module

8.REAR SAM - Rear Signal Acquisition And Actuation Module

9.SRS - Supplemental Restraint System

10.CGW[ZGW] - Central Gateway

11.COU[ZBE] - Audio/COMAND Operating Unit

12.ZAN - Audio/COMAND Display

13.Audio/COMAND - Audio Or COMAND(A2-A2/56-A40/3)

14.IC - Instrument cluster(A1)

15.DCU_LR - Left Rear door(N69/3)

16.DCU_RR - Right Rear door(N69/4)

17.DCU_LF - Left Front door(N69/1)

18.DCU_RF - Right Front door(N69/2)

19.AC - Air Conditioning(N22/7)


We have taken the car to a local garage, and they have done the following:

-Changed / checked fuses and relays for fuel pump

-Changed the fuel filter

-Flushed the fuel lines.



The car did start once but took several cranks.



We are at a stage now where labour costs are adding up. I'd like to ask for suggestions as to other things which you may think may be causing the symptoms / things to try next?



Thank you.

 

You're doing a good job with your diagnosis.
While I am no diesel wizard, I can direct you to read data of:

1. The glow-plug control
2. Fuel rail pressure in ECU
3. (Drive authorization in EIS?)

​​​​​​
People have focused on the diesel oil and filter already. Why don't you dig in glow control now...


Whatever you do, keep your battery charged up.
🤞​​​​​​

 

Thanks very much. OK - first port of call will be to run fresh diagnostics when we get the car back and see if there are any changes in the error codes.
Then will take a look at fuel rail pressure sensor, then down to injectors if needed.

 

... injectors may not be in "brand new" condition BUT they won't keep the engine from starting.

I'd first focus on getting glow satisfied then pressure... the more focuss we stay, the less things get disturbed to potentially bite us later
🤞

 

Thank you Cali Benz Driver - you are totally correct - we want to disturb as little as possible.

Apparently the car starts when brake cleaner is sprayed into the intake... this leads me to think that the glow plug system is okay? Any thoughts?

 

" the car stopped at one point, as it ran out of fuel (but the fuel gauge said it was about 50% full"
I seem to recall that this is an issue with the fuel pump(s) in the tank not managing the transfer of fuel between the two sides of the "saddle" tank ?

 

Hi, yes I agree - I thnk this may be a fuel pump issue myself.

I have purchased the attached fuel pump - I will replace both parts - as this should cure the issue if it is fuel pump related.

I will report back on wether this solves the issue.

Out of interest - is one section a fuel level gauge only and the other a fuel level gauge and pump?
Best

 

use the scanner to read current rail pressure

 

Hello, just a small update. The fuel pump did fix the starting issue, however car had a major coolant leak and misfire, which is slightly above my skill level, so will look to move on as a parts car.
Thank you for your advice and assistance.