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Injection pump > < Removing and installing air filter housing

Fabia Mk1

Removing and installing, testing the injection nozzles
Removing and installing, testing the injection nozzles
Defective injection nozzles cause the following malfunctions:
t  Reduced performance
t  excessively black exhaust smoke
t  increased blue smoke during cold start
t  increased fuel consumption
t  Engine overheating
t  Knocking on one or more cylinders
t  Ignition misfiring
Special tools and workshop equipment required
t  Injection nozzle tester, e.g. -V.A.G 1322-
t  Pressure line, e.g. -V.A.G 1322/2-
t  Ring spanner for injection lines, e.g. -3035-
t  If necessary extractor -MP1-230- and auxiliary tool
Removing
   
–  Remove engine cover. To do so, pull it at the front and rear upwards with a sudden motion.
–  Remove injection lines with ring spanner for injection lines.
–  If necessary unscrew hollow screw for return-flow line (injection nozzle of cylinder 3).
  Note
Always remove injection lines completely. Do not change bending change.
–  Unscrew fixing screws, remove clamp and take out injection nozzles.
–  For jammed nozzles, prepare an auxiliary tool as follows:
Preparing an auxiliary tool
–  Saw off an injection line (e.g. spare part line) approx. 5 cm behind the nozzle union nut.
–  Hard solder an M6 nut to the sawn off line.
–  Thoroughly clean the auxiliary tool, the injection nozzle cannot be used if dirty!
  S10-0115
–  Tighten the union nut of the auxiliary tool on the jammed nozzle and insert the extractor -MP1-230- on the welded nut.
  Note
Store the auxiliary tool with dust protection for future use.
Install
  Note
Always replace the copper seals between the cylinder head and the injection nozzles.
–  Replace the injection nozzles.
–  Pay attention to the correct position of the brackets in the cylinder head.
–  Insert clamp and tighten fixing screws.
Tightening torques:
   Injection lines: 25 Nm
   Hollow screw for return-flow line (cylinder 3): 10 Nm
   Screws for clamp: 20 Nm
Inspection
–  Check injection nozzles → Vehicle diagnostic tester.
   Specified value at idling speed: -2.80 mg/s up to +2.80 mg/s (milligram per stroke)
–  Read off the measured values for the individual cylinders in the measured value block 13.
–  If one or more measured values are outside the tolerance, interchange the injection nozzles (except for the nozzle of cylinder 3).
–  If the fault migrates with the nozzle, replace the injection nozzle.
–  If the fault remains on the cylinder, check the compression → Chapter.
–  If the compression is O.K., replace the relevant connection fitting Pos. 11 with pressure valve and gasket ring on the injection pump → Chapter.
  Note
t  The gasket ring must be removed from the pump with a soft object (plastic, wood) as otherwise the contact surfaces may be scratched.
t  For mileages above 15 000 km replace the connection fitting with pressure valves per set only.
This engine is fitted with 2 spring injection nozzles. This is why the injection of the fuel quantity occurs in 2 steps. If there is a problem with these injection nozzles they must be replaced, as neither a pressure adjustment nor a repair is possible.
  S23-0029
Test injection nozzles with injection nozzle tester, e. g. -V.A.G 1322- and pressure line, e. g. -V.A.G 1322/2-.
  WARNING
When testing injection nozzles make sure the fuel jet does not touch your hands. The fuel under high pressure penetrates the skin and may cause severe injuries.
l  Pressure gauge switched on
–  Slowly press down the pump lever. During commencement of injection, read off the injection pressure. If the injection pressure deviates from the nominal value, replace the injection nozzle.
  S23-0108
New nozzle19 ... 20 MPa
Wear limit17 MPa

Leak check
l  Pressure gauge switched on
–  Press the pump lever slowly down and maintain pressure for 10 seconds at approximately 15 MPa. No fuel may trickle from the nozzle opening.
–  If there is a leak replace injection nozzle.
   

Injection pump > < Removing and installing air filter housing