Audi Workshop Service and Repair Manuals

Checking fuel pump delivery rate - MPI engine from 05.2002 Special tools and workshop equipment required

t  Adapter -V.A.G 1318/17-1- from adapter set -V.A.G 1318/17-

t  Remote control -V.A.G 1348/3 A- with adapter cable -V.A.G 1348/3-2- t  Fuel-resistant measuring container Test requirements l  Battery voltage at least 12.5 V l  Fuel tank at least 1/4 full. l  Ignition off.

Test sequence –  Open fuse box cover on instrument panel (left-side). –  Detach fuse S18 from fuse carrier (3rd fuse in 4th row as seen from top). –  Connect remote control -V.A.G 1348/3 A- with adapter cable -V.A.G 1348/3-2- to left-hand terminal of fuse socket S18. –  Connect clamp to vehicle battery (+). –  Remove filler cap from fuel filler neck.

–  Fold down rear seat bench. –  Fold back lining under rear set. –  Turn fuel delivery unit cover in -direction of arrow- and detach.   WARNING The fuel system is pressurised. Before opening the system place a cloth around the connection. Then dissipate pressure by carefully unfastening the connection.

–  Disconnect fuel return pipe -2- by pressing release tab.   Note The fuel supply pipe -1- and electrical connector remain connected.

–  Fit adapter -V.A.G 1318/17-1- onto disconnected fuel return pipe and hold adapter hose in measuring container.

–  Press remote control button for 15 seconds. –  Compare amount of fuel delivered with minimum delivery shown in diagram (cm3/15 sec.).   Note Voltage at fuel pump with engine stationary and pump running is approx. 2 volts less than battery voltage. If minimum delivery rate is not reached, check for the following causes: t  Fuel lines have been crushed. t  Fuel filter is blocked. t  Fuel pressure regulator; checking → Injection and ignition system; Rep. Gr.24. t  Fuel pump is defective. Assemble in reverse order.