Turn ignition off. To check transfer pump (in tank), remove rear seat. Remove fuel sending unit access cover. Disconnect ignition coil secondary wire and jumper to ground. With transmission in neutral, crank engine for a 3-4 seconds. While the starter is turning and for a few seconds afterwards, an audible sound should be heard at the pump. If not, proceed to step 2).
Activate fuel pumps by removing fuel pump relay and attaching jumper wire between terminals No. 30 battery voltage and No. 87 output to fuel pumps. Terminal identification is molded on fuse/relay panel. If pump does not operate, remove transfer pump wiring harness connector. See Fig 1 .
Using test light, check for voltage between Brown (-) and Green (+) wire at connector. If voltage is present, replace transfer pump. If not, repair open or short circuit in wiring.
If transfer pump operates correctly, remove fuel pump relay jumper wire. Disconnect and plug transfer pump output hose. Attach a hose to pump outlet connector and place other end of hose in a graduated container. Activate fuel pump for 10 seconds.
Minimum fuel flow for CIS-E should be 13.5 ounces (.4 liters). Minimum fuel flow for CIS-Motronic and AFC-Digifant II should be 10.0 ounces (.3 liters). If fuel flow is low, check fuel tank filter for restriction. If okay, replace transfer pump.

Fig 1: Checking Transfer Pump Fuel Volume (Fox & Jetta GLi) (Others Similar)

Courtesy of VOLKSWAGEN UNITED STATES, INC.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Transfer Pump Fuel Volume Check