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Checking intake air preheating > < Checking fuel pressure regulator and holding pressure

Polo Mk4

Checking fuel pressure regulator
Checking fuel pressure regulator
Test prerequisites
l  Fuel pump non-return valve is OK, checking → Chapter.
Test procedure
–  Remove fuse holder cover.
   
–  Remove fuse No. 41 (fuel pump) from fuse holder.
  N24-1481
–  Connect remote control for V.A.G 1348 -V.A.G 1348/3A- with adapter lead -V.A.G 1348/3-2- to contact 41a of fuel pump and battery positive (+).
  WARNING
Fuel system is under pressure! Wear protective glasses and clothing to avoid injuries and skin contact. Before loosening hose connections, wrap a cloth around the connection. Then release pressure by carefully pulling hose off connection.
  N20-0513
–  Pull supply line -1- off output side of fuel filter.
  Note
Press in safety ring to release fuel line.
–  Connect pressure tester -V.A.G 1318- using connector -V.A.G 1318/23- and adapter set -V.A.G 1318/17- as shown.
–  Close pressure gauge shut-off tap (lever at right angles to throughflow direction - position -B-).
–  Operate remote control -V.A.G 1348/3A- to V.A.G 1348 for approx. 10 seconds to fill fuel filter and build-up a system pressure of approx. 3 bar.
–  Watch pressure drop on pressure gauge. After 10 minutes, pressure must not drop below 2.5 bar.
If the pressure drops further:
–  Check line connections for leaks.
If no fault in lines is detected:
–  Renew fuel pressure regulator.
  N20-0532

Checking intake air preheating > < Checking fuel pressure regulator and holding pressure