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Checking fuel delivery volume of metering pump with auxiliary heater switched on > < Complete filling of fuel pipe

A3 Mk2

Checking:
Checking:
Test preparation performed → Chapter and fuel pipe completely filled → Chapter
–  Select auxiliary heater control unit -J364- in “Guided Fault Finding” function → Guided Fault Finding function of vehicle diagnostic, testing and information system VAS 5051.
–  Check delivery rate of metering pump -V54- → Guided Fault Finding function of vehicle diagnostic, testing and information system VAS 5051.
  Note
t  With the auxiliary heater control unit -J364- currently fitted, the maximum value which can be entered is “255”.
t  When checking the delivery rate, the metering pump -V54- is activated for 200 seconds at 7 hertz (7 pulses per second).
t  The metering pump -V54- activation time is entered in seconds in the adaption channel. When the “Pipe filling” function is next selected in “Basic setting”, the metering pump -V54- is activated 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  In the “Pipe filling” routine of the “Basic setting” function, the metering pump -V54- is activated at a frequency of 7 hertz (7 pulses per second). Delivery rate set in metering pump is approx. 0.031 ml per stroke (0.031/1000 litre).
t  Depending on auxiliary heater control unit -J364-, rounding error on conversion following entry of encoded display value, e.g. “200” may cause the following display to appear “Note: Value 200 to be stored, value 199 actually stored”. If this display appears, enter e.g. “201” instead of “200” if necessary to store the exact value and confirm the display.
t  Values entered which are not within the specified limits are displayed but not implemented.
t  If the value entered is too high or too low, the display is automatically reset (to the lowest or highest value still permitted).
–  Wait until set time has elapsed and metering pump -V54- is no longer activated.
  Note
Depending on control unit version, tester display switches from “Pipe filling” to “End” or “Function unknown or cannot be implemented at present”.
–  Terminate Guided Fault Finding.
   
–  Measure the fuel delivery rate of the metering pump -V54- on completion of the “Pipe filling” routine in the “Basic setting” function.
Specification:
44 ml +/-4 ml (permissible tolerance range 39 to 49 ml)
  Note
t  One millilitre (ml) = 1/1000 litre or cm3.
t  If the quantity of fuel delivered is not within the tolerance range, check the fuel pipe (from the fuel tank via the metering pump to the auxiliary heater) for damage and proper routing → Chapter. If no fault is detected, renew metering pump -V54- → Chapter.
t  If the fuel delivery volume is within the tolerance range, check the operation and activation of the fuel shut-off valve -N109- → Chapter of auxiliary heaters with fuel shut-off valve -N109- (only on vehicles with diesel engine; introduction not yet finalised → Electronic parts catalogue).
t  The installation of a fuel shut-off valve -N109- is currently only planned for vehicles with diesel engine (only installed on VW vehicles; introduction for Audi vehicles not yet finalised) → Electronic parts catalogue
t  Currently no auxiliary heater with a fuel shut-off valve -N109- is installed in Audi A3 vehicles during production (introduction not yet finalised). However it is possible that individual vehicles have been retro-fitted with an auxiliary heater with a fuel shut-off valve -N109-; therefore it is important to pay attention to the correct version.
t  For auxiliary heaters with fuel shut-off valve -N109- (only on vehicles with diesel engine; introduction for Audi A3 vehicles not yet finalised → Electronic parts catalogue), fuel can only be delivered into auxiliary heater if fuel shut-off valve -N109- is activated and thus opened (checking operation and activation of fuel shut-off valve -N109- → Chapter).
t  If there are problems starting the auxiliary heater although the fuel delivery volume is OK, check the CO2 content in the exhaust gas → Chapter.
t  If the fuel delivery volume is within the lower tolerance range (less than 40 ml) and there are problems starting the auxiliary heater or if there is poor heating output, renew the metering pump -V54- if necessary.
  A82-0474
t  On vehicles with petrol engine, connection -F- of burner element is fitted with a filter and a restrictor → Chapter. If this filter is clogged, metering pump cannot convey fuel into combustion chamber. If necessary, check this filter as follows for blockage → Chapter (checking fuel delivery of metering pump with auxiliary heater switched on).
t  On vehicles with diesel engine, fuel is preheated by way of fuel pre-heating heater element -Z66- before entering combustion chamber ( → Chapter). If fuel is not preheated, auxiliary heater starting problems may be encountered at low ambient temperatures.
–  Re-install all components fitted on completion of envisaged work.
–  Start engine.
–  With the engine running, start the auxiliary heater by way of the “Auxiliary heater on” routine in the “Basic setting” function (the auxiliary heater must be allowed to operate for a short period to reset the value displayed in the measured value block to the initial value) → Guided Fault Finding function of vehicle diagnostic, testing and information system VAS 5051.
–  Once the auxiliary heater is in full-load operation, switch off the auxiliary heater via the “Auxiliary heater off” routine in the “Basic setting” function → Guided Fault Finding function of vehicle diagnostic, testing and information system VAS 5051.
–  Terminate Guided Fault Finding and switch off ignition.
  A82-0474

Checking fuel delivery volume of metering pump with auxiliary heater switched on > < Complete filling of fuel pipe