Volkswagen CJDA Workshop Manual page 401

– Run engine at idling speed for several minutes - do not
press accelerator - and then switch engine off again. (Fuel
system bleeds itself).
– Check the entire fuel system for leaks.
Renew the affected component if leakage still occurs after tight-
ening to the correct torque.
– Perform a test run, accelerating to full throttle at least once.
Then check high-pressure part of fuel system again for leak-
age.
Note
If there is any air left in the fuel system, the engine may switch
to the limp mode during the road test/test run. Switch off the en-
gine and clear the event memory
ry. Then, continue road test/test run.
1.17 Checking pressure retention valve in
fuel return line
The pressure retention valve maintains a residual pressure of
approx. 10 bar in the return lines.
This residual pressure is required for the control function of the
piezo injectors.
Workshop Manual for Diesel Engine (2.0 l/36-75 kW_EA 189) 05.2015
⇒ P age
26, read event memo-
Industriemotoren - Industrial Engines 2009 ▶
1 Repairing diesel direct injection system
3
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