Checking delivery rate

WARNING: This page is about a different car, the 2004 Volkswagen R32. However, it is still accessible from the selected car via links, so may be relevant.

Test conditions

Voltage supply OK.
Remote control V.A.G 1348/3A connected

Test sequence

Remove fuel filler cap from fuel filler tube.

CAUTION: Fuel supply lines are under pressure! Wear eye protection and protective gloves to avoid injuries and skin contact with fuel. Before removing from hose connection wrap a cloth around the connection. Then release pressure by carefully pulling hose off connection.

Fig 1: Identifying Supply Line And Return Line

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Disconnect supply hose - 3 - (with white marking) and collect fuel that may leak out with a cloth.

NOTE:

Press buttons on hose couplings to do this.

Fig 2: Pressure Gauge V.A.G 1318 Connected To Fuel Supply Line Using Fuel Line Feed Adapter V.A.G 1318/23 And Adapter V.A.G 1318/17

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Connect pressure gauge V.A.G 1318 to fuel supply line using fuel line feed adapter V.A.G 1318/23 and adapter V.A.G 1318/17.
Install hose adapter V.A.G 1318/16 onto adapter V.A.G 1318/11 on pressure gauge V.A.G 1318 and hold hose in a measuring container.
Open shut-off tap on pressure gauge V.A.G 1318. The lever then points in direction of flow.
Operate remote control V.A.G 1348/3A. Slowly close shut-off tap, until pressure gauge shows 3 bar. From this point on do not move position of shut-off tap.

Empty the measuring container.
Delivery rate of Fuel Pump (FP) is dependent on battery voltage. Therefore, connect multimeter V.A.G 1715 to vehicle battery using adapter cables from connector test kit V.A.G 1594C.
Operate remote control for 30 seconds and measure battery voltage.

Fig 3: Fuel Delivery Chart

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Compare the quantity of fuel delivered with specification.

- * ⁾ - Minimum delivery rate cm ³ /30 seconds

- ** ⁾ - Voltage at fuel pump with engine stopped and pump running (approx. 2 volts less than battery voltage).

Example:

During the test, a voltage of 13 volts is measured at the battery. As the voltage at the pump is approx. 2 volts less than the battery voltage then this will equate to a minimum delivery of 1,100 cm ³ /30 s.

If minimum delivery rates are not obtained:

Check fuel lines for possible restrictions (kinks) or blockages.

Fig 4: Connecting Pressure Gauge VAG 1318 To Hose With Adapter VAG 1318/17 To Fuel Filter

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Pull off supply hose - 1 - from fuel filter inlet.
Connect pressure gauge V.A.G 1318 to the hose using adapter V.A.G 1318/17.
Resume testing the delivery quantity.

If minimum delivery rate is now obtained:

Replace the fuel filter:

If minimum delivery rate is again not obtained:

Remove fuel delivery unit and check fuel strainer for soiling.

Only when up to now no malfunction has been detected:

Replace fuel delivery unit.

If delivery rate has been attained but nevertheless you suspect a fuel supply system malfunction (e.g. intermittent failure of fuel supply system):

Check current draw of fuel pump as follows:
Reconnect all disconnected fuel lines.

Fig 5: Multimeter V.A.G 1715 Connected To Wire For Contact 1Of 4-Pin Connector Using Current Pick-Up Clamp.

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Connect multimeter V.A.G 1715 to wire (arrow) for contact 1of 4-pin connector using current pick-up clamp.
Start engine and run at idle speed.
Measure current draw of fuel pump. Specification: max. 8 amps.

NOTE:

If malfunction in fuel system is sporadic, test can also be performed during a road test, but a second person is required.

If current draw is exceeded:

Fuel Pump (FP) faulty, replace fuel delivery unit, refer to Fuel delivery unit, removing and installing .