Car fuel injection system Mercedes S-Class (W126)

The principle of operation of the fuel injection system
1. Air flow meter. 2. Base plate (disk). 3. Starting fuel valve. 4. Nozzle 5. Idle mixture adjusting screw. 6. Safety switch. 7. Temperature switch. 8. Additional air...

Inspection, testing and adjustment of the fuel injection system
Caution: When working on the fuel injection device, be extremely clean. Before removal, the corresponding parts should be cleaned with gasoline. The system is under high...

Checking the tightness of the injection system connections
If a hot engine is difficult to start, then it is necessary to check the seals of the injection system. With the air filter removed, check the fuel connections in the...

Checking and adjusting idle speed and CO content
Warm up the engine to an operating temperature of at least 60°C. Attention: Do not adjust the idle code on a very hot engine. Connect RPM and CO meters according to...

Throttle link adjustment
Check for wear, bending and ease of movement of the rods. Lubricate all moving parts with oil. Disconnect connecting rod (arrow) on the return lever. Move the throttle...

Full Throttle Limiter Adjustment
Press the gas pedal all the way (full throttle position) and fix in this position with a suitable board inserted between the pedal and the seat (for vehicles with manual...

Removal, installation and check of a nozzle of start of the cold engine
The cold start injector provides additional fuel to the intake manifold during a cold start. Injector failure causes engine starting difficulties (both cold and hot),...

Removal, installation and check of the thermal time switch
The thermal time switch limits the injection time of the cold start injector depending on the engine temperature. The temperature at which the thermo-time switch is...

Checking the additional air damper
When the engine warms up, it needs an increased supply of air-fuel mixture, which is determined by the position of the throttle. To do this, with the help of an...

Checking and adjusting the air flow meter damper
If the flow meter damper is set high, the engine will not start. Incorrect adjustment of the rest position of the flow meter damper will cause a warm engine to start...

Checking the cold start valve
During starter operation, the cold start valve additionally injects gasoline into the intake tract. In this case, the duration of injection depends on the temperature of...

Tempomat adjustment
Attention: If in vehicles with a cruise control shocks appear when using the cruise control at speeds above 60 km/h. then it is necessary to remove the tempomat relay...

Checking the Temperature Sensor
From the NTC sensor, the device that controls the injection device receives operational information about the temperature of the engine. The electrical resistance of the...

Fuel pump check
Attention: Observe fire safety rules, do not work with open flame! To check the pump flow, the tank must be at least half full. Remove the fuel pump relay. Connect a...

Removal and installation of the fuel pump
Removing Raise the car from behind. Disconnect ground from battery. Open and close the gas tank cap to equalize the pressure. Unscrew the protective cover. Clamp the...

Diagnosis of malfunctions of the injection system
Before using the table to determine faults, the following conditions must be met: start-up errors are excluded; both with a cold and a warm engine, the gas pedal must be...