Mercedes-Benz E W211 Butterfly Body 3.00 A6420900270 A6420901037

#127

Genuine used Mercedes-Benz E-Class W211 3.0 CDI electronic throttle / intake butterfly body, carrying references A6420900270 and A6420901037. This electronically controlled intake component is used with the OM642 3.0 V6 CDI diesel engine and regulates intake airflow as part of the engine-management and EGR system.

Mercedes Part Number: A6420900270

Additional / Replacement Reference: A6420901037

OE Format: A 642 090 02 70 / A 642 090 10 37

Part Type: Electronic Throttle Body / Intake Butterfly Valve / Throttle Valve Actuator

Engine Family: OM642

Engine Size: 3.0 V6 CDI Diesel

Position: Engine Intake System

Manufacturer: Mercedes-Benz / OEM Supplier

Condition: Genuine used part

Compatibility

Suitable for selected Mercedes-Benz E-Class W211 / S211 3.0 CDI models equipped with the OM642 V6 diesel engine, including applications such as:

* Mercedes-Benz E 280 CDI – selected OM642 versions

* Mercedes-Benz E 300 CDI – selected versions

* Mercedes-Benz E 320 CDI – selected OM642 versions

* Mercedes-Benz E-Class W211 Saloon

* Mercedes-Benz E-Class S211 Estate

* Approx. mid/late-2000s OM642 applications

The A642… numbering identifies this as an OM642-family component, but Mercedes used several revisions of the throttle/intake valve across different OM642 vehicles.

The original numbers, electrical connector and physical configuration should therefore be compared before ordering.

Technical Information

Unlike the throttle body on a petrol engine, the diesel throttle butterfly is not primarily responsible for controlling engine speed.

The OM642 diesel engine normally regulates power through fuel quantity, while this electronic butterfly valve is used by the engine-management system for functions including:

* Intake airflow management

* EGR system operation

* Creating the required pressure differential for EGR flow

* Emissions control

* Smooth engine shutdown

* Intake-system management during different operating conditions

An electric actuator integrated into the assembly moves the butterfly plate according to commands from the engine ECU.

OM642 Intake & EGR System Information

The OM642 uses electronically controlled intake and exhaust-gas-recirculation components to manage emissions and combustion.

During EGR operation, the engine ECU can partially close the intake butterfly.

This changes intake pressure and helps draw the required quantity of exhaust gas through the EGR system and back into the intake.

The throttle body therefore works closely with components including:

* Engine ECU

* EGR valve

* EGR cooler

* Mass Air Flow sensor

* MAP / boost-pressure sensor

* Turbocharger system

* Intake manifolds

* Swirl flap system

A fault elsewhere in this system can sometimes generate symptoms that appear to indicate a defective throttle body.

Electronic Actuator Information

The butterfly plate is operated by an integrated electric actuator.

The ECU commands a required valve position and monitors its operation using position feedback.

Problems can occur because of:

* Internal electric motor failure

* Worn actuator gears

* Position-sensor failure

* Electrical connection problems

* Carbon/oil contamination around the butterfly

* Mechanical sticking of the valve

Oil vapour from the crankcase ventilation system combined with EGR deposits can create contamination within the diesel intake system over time.

Common Symptoms of a Faulty Throttle Body

Possible symptoms include:

* Engine-management warning light

* Reduced engine power

* Limp-home mode

* Poor throttle response

* Irregular engine operation

* Increased emissions

* EGR-related fault codes

* Intake-airflow plausibility faults

* Throttle-position faults

* Butterfly valve sticking

* Engine shutting down less smoothly

* Actuator motor not operating

* Intermittent electrical faults

A sticking butterfly can sometimes operate intermittently before complete failure.

Important Diagnostic Information

Before replacing the throttle body, carry out a complete diagnostic scan.

Check:

* Throttle actuator fault codes

* Requested versus actual throttle position

* Electrical connector

* Wiring continuity

* ECU power/control signals

* EGR valve operation

* MAF readings

* MAP / boost-pressure readings

* Intake hoses

* Boost leaks

* Carbon contamination

* Intake manifold condition

* Swirl flap operation

An EGR, airflow or boost-system fault can sometimes generate secondary throttle-related codes.

For this reason, replacing the throttle body purely on the basis of a generic engine-management warning light is not recommended.

Carbon & Oil Contamination

Some oily residue inside an OM642 diesel intake system can be normal due to crankcase ventilation.

Heavy deposits, however, can interfere with butterfly movement.

If excessive contamination is found, related intake and EGR components should also be inspected rather than simply replacing the throttle body.

Do not force the electronic butterfly mechanism manually, as excessive force may damage the internal actuator/gearing.

Installation

Before installation:

* Switch off the ignition

* Disconnect the battery where required by Mercedes workshop procedure

* Inspect the electrical connector

* Check intake hoses and seals

* Inspect mating surfaces

* Replace damaged seals/gaskets where necessary

* Ensure no debris enters the intake

After installation:

* Check all intake connections

* Check for air/boost leaks

* Reconnect the electrical connector securely

* Clear relevant stored fault codes

* Test actuator operation with suitable diagnostic equipment where required

* Confirm correct engine operation

Programming / Coding

Direct vehicle-specific coding is normally not required when fitting the correct matching throttle body.

However, depending on ECU/software configuration, diagnostic adaptation or actuator teach-in may be required or beneficial after replacement.

A Mercedes-compatible diagnostic system such as Xentry/STAR can be used to check actual/commanded throttle position, run actuator tests and perform available adaptation procedures.

Important Compatibility Note

Please compare before ordering:

* A6420900270

* A6420901037

* Complete number printed on the original unit

* OM642 engine variant

* Electrical connector

* Connector pin configuration

* Butterfly housing design

* Intake pipe connections

* Mounting points

* Vehicle VIN / production date

Mercedes used numerous revisions of OM642 intake components, and parts that appear almost identical externally are not automatically interchangeable.

Matching the OE references with the original component or checking against the VIN is strongly recommended.

Condition

Genuine Mercedes-Benz used electronic engine component.

The item may show normal signs of previous use, including:

* Surface marks

* Scratches

* Oil residue

* Carbon deposits

* General signs of removal/storage

Please inspect all listing photographs carefully for the exact condition of the butterfly plate, housing, electrical connector and mounting points.

Any identifying colour/security markings applied to the part must remain intact in the event of a return.

Ideal genuine replacement for a faulty, sticking, damaged or non-operating Mercedes-Benz W211 3.0 CDI OM642 electronic throttle / intake butterfly body, provided A6420900270 / A6420901037 correspond with the original component.