Open Fuel Injectors, Checking: Procedure
-- Remove the engine cover, refer to ENGINE COVER, REMOVING AND INSTALLING .
-- Clean all fuel rail connections with engine or brake cleaner and dry off.
Danger of malfunction caused by dirt.
- Observe, refer to FUEL SYSTEM SAFETY PRECAUTIONS .
-- Open the clamp -arrow- and remove the fuel supply hose -1- from the banjo bolt.
-- Connect the Hand Vacuum Pump :VAS6213 on the fuel supply hose -1-.
Do not pry the fuel supply hose -1- through the Hand Vacuum Pump :VAS6213 adapter.
-- Generate a vacuum of -500 mbar with the Hand Vacuum Pump :VAS6213 .
Fuel injectors are OK when the pressure remains constant for about 30 seconds.
If an injector is faulty, then the pressure will drop to 0 bar again within 2 to 3 seconds.
If the pressure drops, check the individual cylinder banks fuel injectors.
Check One Cylinder After Another.
Starting with cylinder 1.
-- Remove the fuel supply hoses from the fuel injectors to be checked by pressing both retaining straps down while pulling up on the center piece to release -arrow-.
The illustration shows cylinder bank 1.
-- Connect the clean adapter that has been cleaned out using compressed air to the fuel return line connection on the injector that is being checked.
-- A vacuum pressure of -500 mbar is applied using the Hand Vacuum Pump :VAS6213 .
Fuel injectors are OK when the pressure remains constant for about 30 seconds.
If an injector is faulty, then the pressure will drop to 0 bar again within 2 to 3 seconds.
Repeat the test if necessary. Watch the Hand Vacuum Pump :VAS6213 for a loss of pressure.
-- Replace any defective fuel injectors, refer to FUEL INJECTORS, REMOVING AND INSTALLING .
-- Secure the fuel supply hose with a new clamp on the banjo bolt.