1999 E300TD Randomly Stalls

[scottsails2]

My 1999 E 300 Turbo Diesel (210.025) starts without hesitation but, it will randomly stall during normal driving. Sometimes if I keep pressing the accelerator it will stumble but keeps running in the limp mode. When I pull of the road it will normally start again on the third attempt. I have replaced both fuel filters and every fuel line from the firewall forward. I am confident it is not a fuel related problem. I have changed the Overload Relay Fuse Box Unit (K40) and the Fuel Shut-off Actuator (Y1/1). I have removed and inspected the connecting plugs on the Engine Control Module (IFI), and whatever the module (?) just forward of the (IFI) is in the same covered box and the injection pump disconnection plug mounted to the firewall. Nothing has solved the random stalling for six months now. I have read all the post and accomplished everything they mentioned. I have the Star Service Manual CD for this car. The OBD code that I have is P0200 which is the fuel actuator circuit? I could use some assistance with the diagnostic test to confirm the item to check/change. Thank you, Scott

[dtf]

Sounds like you have fuel system covered - is your air intake clogged?

[scottsails2]

dtf, Thank your for your input I will inspect the intake system. Got code P0200 Injector Circuit Malfuntion - fuel quantity, fuel rack postion sensor or IFI control module. MBDOC suggested CPS so I am going to do some meter reading and hopefully that will show somthing. Scott

[scottsails2]

UPDATE: The OBD code that I have is P0200 Injector Circuit Malfunction which has these other codes listed. I do not have a MB test connector so I could use some assistance with the diagnostic test to confirm the items to be check. Thanks, Scott
P1220 Fuel quantity actuator (Y23/1) (signal to fuel quantity actuator)
P1222 Accelerator Pedal Position Sensor (R25/2)
P1223 Fuel rack position sensor (Y23/1/1) (signal from fuel rack position sensor)
P1611 Engine control Module – internal reference voltage (N3/7)
P1613 Engine control Module – internal check for delayed shutoff (N3/7)
P1614 Engine control Module – microprocessor / fuel calculation (N3/7)
P1617 Engine control Module – EEPROM or incorrectly coded. (N3/7)

[scottsails2]

My DVD has a diagnostic section that lists all the ODB codes. P0200 is the master code and the list gives you the codes that can caused the master code to register giving you the check engine light. I removed the back shell of the Engine Control Module (N3/7) connector and used a multi-meter to read the wiring and arrived with the following readings. The problem is random, with the car operating normally at this time it is hard to say if the slight imperfections would cause the car to stall. Please review the information and give me your input.
P1220 Fuel Quantity Actuator (Y23/1) (Adjustment Solenoid) Voltage was a little low.
Ignition: On, Nominal Value: >4.0 volts for maximum of 30 seconds.
Ignition and connector: Off, Nominal Value: 1.0 + or - 1.4 ohms.
Reading from 36 to 37 was 3.75 volts for 30 seconds. Resistance was 0.7 ohms.
Reading from 54 to 37 was 3.73 volts for 30 seconds. Resistance was 0.7 ohms.
P1222 Accelerator Pedal Position Sensor (R25/2) Voltage was good thru the range of travel.
Ignition: On, Nominal Value at idle: 0.2 + or - 0.5 volts.
Ignition: On, Nominal Value at full load: 3.7 + or - 4.8 volts.
Idle was 0.315 volts.
Full load was 4.41 volts.
P1223 Fuel Rack Position Sensor (Y23/1/1) Resistance was a little high.
Ignition: On, Nominal Value: 2.2 - 2.7 volts.
Reading from 19 to 9 was 2.5 volts.
Reading from 19 to 10 was 2.5 volts.
Ignition and connector: Off, Nominal Value first two test points: 20 - 25 ohms.
Ignition and connector: Off, Nominal Value second two test points: 40 - 50 ohms.
Reading from 46 to 9 was 26.3 ohms.
Reading from 10 to 9 was 46.8 ohms.
P1335 CKP Sensor (L5/6) (Crank Position Sensor) Voltage reading was good.
Engine at idle, Nominal Value: >0.3 volts AC.
Reading from 28 to 20 was 1.20 volts AC.
Revving engine caused the voltage to increase.
Ignition and connector: Off, Nominal Value: 610 - 1300 ohms.
Reading from 28 to 20 was 686 ohms.
I have connected a multi-meter to the Fuel Shut Off actuator connections to see if the voltage (11 - 14) drops off during one of the stalls. If I lose power, I will focus on the Engine Control Module (N3/7). If no power drop, I will focus on the Fuel Quantity Actuator (Y23/1). Thanks, Scott

[anghrist]

Odd. This is either systemic or something really simple. There are very few things that would cause a stall (lack of fuel, lack of compression, lack of air).

I know that the EGR vacuum modulator can cause stumble/near stall behavior if the vent on the bottom gets blocked or clogged.

Other than that, I would check the integrity of the SOV electrical connection.

[pimpernell]

Originally Posted by scottsails2

UPDATE: The OBD code that I have is P0200 Injector Circuit Malfunction which has these other codes listed. I do not have a MB test connector so I could use some assistance with the diagnostic test to confirm the items to be check. Thanks, Scott
P1220 Fuel quantity actuator (Y23/1) (signal to fuel quantity actuator)
P1222 Accelerator Pedal Position Sensor (R25/2)
P1223 Fuel rack position sensor (Y23/1/1) (signal from fuel rack position sensor)
P1611 Engine control Module – internal reference voltage (N3/7)
P1613 Engine control Module – internal check for delayed shutoff (N3/7)
P1614 Engine control Module – microprocessor / fuel calculation (N3/7)
P1617 Engine control Module – EEPROM or incorrectly coded. (N3/7)

From some of the codes you listed, your CCU may need to be replaced, or re-programed.








Engine Control Module Description

The engine control module (ECM) interacts with many emission related components and systems. The ECM also monitors emission related components, and systems, for deterioration. The on-board diagnostics monitor the system performance and a diagnostic trouble code (DTC) sets if the system performance degrades.
The malfunction indicator lamp (MIL) operation and DTC storage are dictated by the DTC type. DTCs are ranked as a Type A, B or C. Types A and B DTCs are emissions related. A Type C DTC is non-emissions related.
The ECM is the control centre of the engine controls system. The ECM controls the following components:

• The fuel injection system

• The glow plug control module

• The emission control systems

• The fuel filter heater

• The on-board diagnostics

• The A/C and fan systems

• The throttle plate actuator

• The turbocharger boost actuator

The ECM constantly monitors the information from various sensors and other inputs, and controls the systems that affect the vehicle performance and emissions. The ECM also performs diagnostic tests on various parts of the system. The ECM can recognise operational problems and alert the driver via the MIL. When the ECM detects a malfunction, the ECM stores a DTC. The condition area is identified by the particular DTC that is set. This aids the technician in making repairs.
ECM Function

The engine control module (ECM) can supply 5 V, 12 V, or ground to various sensors or switches. Voltage is supplied through pull-up resistors to the regulated power supplies within the ECM. In some cases an ordinary shop voltmeter will not give an accurate reading due to low input resistance. A DMM with at least 10 MΩ input impedance is required in order to ensure accurate voltage readings.
The ECM controls the output circuits by controlling the ground or the power feed circuit through the transistors or a device called an output driver module.
EEPROM

The electronically erasable programmable read only memory (EEPROM) is a permanent memory that is physically part of the engine control module (ECM). The EEPROM contains program and calibration information that the ECM needs in order to control the powertrain operation.

[EdzBenz]

My E300 is also stalling. However, it is only stalling when the brakes are applied. Otherwise the engine runs well. Its not throwing any codes either. I have my mechanic looking it over this week. I'll keep you updated if I find out anything on my end as to what the fix was. It is probably an electrical gremlin of the sort.

[scottsails2]

No news is good news! The car has not stalled during this past week of driving. If it does not stall for another week, then I must have fixed something. I think while taking the readings at the different wire locations with the meter probes I must have improved the pin and socket continuity. Thanks for your input. Scott