Open PIEZO Injectors, Checking
Special Tools And Workshop Equipment Required
- Hand Vacuum Pump:VAS6213
- Make an adapter for the return line.
This procedure contains mandatory replaceable parts. Refer to component overview prior to starting procedure.
Mandatory Replacement Parts
- O-ring - Fuel lines
Open injector means: the nozzle needle does not close all of the way and fuel leaks into the cylinder.
- Follow the guidelines for a clean working environment when working on the fuel system. Refer to CLEAN WORKING CONDITIONS AND FUEL SYSTEM WORK INSTRUCTIONS .
- Always follow these rules before and during work.
-- Erase the fault stored in the DTC memory using the Vehicle Diagnostic Tester.
-- Remove the engine cover. Refer to ENGINE COVER, REMOVING AND INSTALLING .
-- Clean all connections, for example with commercially available detergent, before removing.
Maintain clean working conditions. Contamination must not enter the fuel system.
Check one cylinder after another.
-- Dry all cleaned components.
Begin with cylinder 1.
-- Remove the fuel supply hoses from the fuel injectors by pressing both retaining straps down while pulling up on the center piece to release in direction of -arrow- .
-- 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 (-7.25 psi) is applied using the Hand Vacuum Pump:VAS6213 .
If the injectors are OK, then the pressure will remain above 30 s.
If the injectors are 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 faulty injectors. Refer to PIEZO INJECTORS, REMOVING AND INSTALLING .