SEAT Workshop Service and Repair Manuals

The fuel pressure regulator controls the fuel pressure dependent upon intake manifold pressure.

Special tools, testers, measuring instruments and auxiliary items required

• ◆ Pressure tester V.A.G 1318
• ◆ Adapter 1318/10
• ◆ Hose V.A.G 1318/1

Test conditions

• ● Fuel pump delivery rate OK, checking:

=> Rep. Gr. 20; Removing and installing parts of fuel system; checking fuel pump

Test sequence

• ‒ → Remove fuel manifold sealing plug -1- and connect pressure gauge V.A.G 1318 with adapter V.A.G 1318/10 to fuel manifold.
  The cut-off tap on the pressure gauge must be closed (lever -arrow- at right angles to direction of flow).
• ‒ Start engine and run at idling speed.
• ‒ Check fuel pressure.
      Specification: Approx. 2.5 bar

• ‒ → Pull vacuum hose off fuel pressure regulator on intake manifold upper part -arrow-. The fuel pressure must increase to
      approx. 3.0 bar.
• ‒ Switch off ignition

• ‒ Check for leaks and holding pressure by watching pressure drop on gauge. After 10 minutes there must be
      a residual pressure of
  at least 2 bar.

If the holding pressure drops below 2 bar:

• ‒ Start engine and run at idling speed.
• ‒ After the pressure has built-up switch off ignition and at the same time clamp-off the return pipe -with blue markings- on fuel manifold.
• ‒ Watch pressure drop on gauge.

If the pressure does not drop:

• ‒ Renew fuel pressure regulator.

If the pressure drops again:

• ‒ Check fuel pump non-return valve:

=> Rep. Gr. 20; Removing and installing parts of fuel system; checking fuel pump

• ‒ Check pipe connections, O rings on fuel manifold and injectors for leaks.
• ‒ Check pressure gauge for leaks.