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Exploded view of metering pump V54 > < Complete filling of fuel pipe

A4 Mk3

Checking fuel delivery rate
Checking fuel delivery rate
l  Test preparation performed → Chapter and fuel pipe completely filled with fuel → Chapter
–  Select the auxiliary/supplementary heater “Guided fault-finding” function on the Vehicle diagnostic, testing and information system → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
  Note
t  If the auxiliary heater does not respond, switch on the ignition if applicable before selecting the supplementary heater control unit -J364- again.
t  Auxiliary heater guided fault-finding can only be started with the ignition switched on or within a specified period after switching off the ignition or following the last exchange of data between the tester and a control unit (the data bus diagnostic interface -J533- is not constantly active).
–  Check the fuel delivery rate of the metering pump -V54- → "Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051.
  Note
t  There may be several reasons for the display “Function unknown” or “Cannot be implemented at present” appearing in the display zone → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function”.
t  With the supplementary heater control unit -J364- fitted at present, the maximum value which can be entered is “255”.
t  The metering pump -V54- actuation time for “Pipe filling” is entered in seconds in the adaption channel. When the “Pipe filling” routine is next selected in the “Basic setting” function, the metering pump -V54- is actuated for this period. The “Pipe filling” function can however only be performed in “Basic setting” if this has been enabled in a further adaption channel → "Guided fault-finding" function of vehicle diagnostic, testing and information system VAS 5051.
t  For checking the fuel delivery rate of the metering pump -V54-, the pump is actuated in the “Pipe filling” routine of the “Basic setting” function in accordance with the time set (in this case for 240 seconds).
t  In the “Pipe filling” routine of the “Basic setting” function, the metering pump -V54- is actuated at a frequency of 8 hertz (8 pulses per second). The fuel delivery rate set in the metering pump -V54- is approx. 0.028 ml per stroke (0.029 ml per stroke or 0.029/1000 litres for vehicles with a diesel engine and 0.027 ml per stroke or 0.027/1000 litres for vehicles with a petrol engine).
t  The following illustration shows the positions of the components on an Audi A5 Coupé. The layout differs slightly on the Audi A4 and Audi Q5. On these other vehicles the work is however to be performed in the same manner as described for the Audi A5 Coupé.
The metering pump -V54- is actuated in the “Pipe filling” function for 240 seconds at a fixed clock frequency.
–  Wait until the time set for the “Pipe filling” routine of the “Basic setting” function has been completed and the metering pump -V54- is no longer actuated.
   
–  Measure the fuel delivery rate of the metering pump -V54- in the graduated beaker -B-.
Specifications:
Diesel - 51 to 62 ml
Benzin - 48 to 58 ml
  Note
One millilitre (ml) = 1/1000 litre or cm3.
If the fuel delivery is outside the tolerance range:
–  Check the fuel pipe (from the fuel tank via the metering pump -V54- to the auxiliary heater) for damage and proper routing → Chapter.
–  Check operation of the fuel pre-supply pump -G6- → Vehicle diagnostic, testing and information systemVAS 5051/, “Guided fault-finding function” and → Chapter.
–  If no fault is found, replace the metering pump -V54- → Chapter.
–  In the event of auxiliary heater starting problems despite a correct fuel delivery rate, check the CO2 content in the exhaust gas → Chapter.
–  If the fuel delivery rate is in the lower tolerance range (less than 52 ml for a diesel engine and less than 49 ml for a petrol engine) and auxiliary heater starting problems are encountered, replace the metering pump -V54- if applicable → Chapter.
  A82-10104

Exploded view of metering pump V54 > < Complete filling of fuel pipe