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Fuel System Pressure

  1. Ensure engine is at normal operating temperature. Using Adapter (VW 1318/4), connect Fuel Pressure Tester (VW 1318) to fuel distributor. See Fig 1 . Close fuel pressure valve.
    Fig 1: Connecting Fuel Pressure Tester
    G94376Courtesy of AUDI OF AMERICA, INC.
  2. Remove fuel pump relay from fuse panel and connect Remote Control (US4480/3) in fuse panel fuel pump relay cavity. Ensure fuse No. 13 on fuse panel is good.
  3. Open valve on pressure tester and energize fuel pump with remote control. Fuel pressure should be 89-94 psi. (6.3-6.6 kg/cm2 ). If fuel pressure is too high, carefully remove fuel return line from fuel pressure regulator and place in container.
  4. Repeat test. If fuel pressure is still too high, replace fuel pressure regulator. If pressure is okay, check return line for obstruction or kinks and repair or replace as necessary.