Audi A6 C5: How to Replace Fuel Pump

The fuel pump is the device that pumps fuel from your Audi A6 C5's gas tank to your engine. Read on to learn how to replace your faulty pump.

By Bassem Girgis - April 6, 2016

This article applies to the Audi A6 C5 (1998-2004).

The Audi A6 C5, like all other vehicles, is equipped with a fuel pump. This device is designed to pump the fuel from your gas tank, through your fuel filter, and to your engine. A failed fuel pump can affect your car's performance. You could feel hesitation, sluggish feel, and if it completely fails, you won't have any gas going to your engine, which means your car won't start. This guide will help you in replacing the fuel pump in the Audi A6 C5, and luckily, your fuel pump is located under the rear seat, and easily accessible. Read on to learn how to replace the fuel pump in your Audi A6 C5.

Materials Needed

Two flat head screwdriver
Phillips screwdriver
Wrench
Rubber mallet

Step 1 – Disconnect battery

Disconnect the negative (black) battery terminal. Use your wrench to loosen its nut, then pull it apart and wrap it in a towel; this ensures it doesn't touch anything metal and create a spark.

audi a6 c5 c6 v6 fuel pump remove replace change how to location — Figure 1. Disconnect negative (black) battery terminal.

Step 2 – Remove rear bench

The fuel pump is located under the rear bench, on the passenger side. To remove the rear bench, grab a hold of it from the front part, then yank it out. It is held in place by some clips, so expect a sturdy yank before it can come off. Once it comes off, lift it slightly and disconnect the electrical harnesses; you will only have those if your car is equipped with rear seat warmers.

Figure 2. Remove rear bench.
Figure 3. Disconnect electrical connections (if equipped).

Step 3 – Remove fuel pump panel

There is a circular panel covering the fuel pump under the bench seat, on the passenger side. Remove the three Phillips screws holding it in place, then remove it out of the way to reveal the fuel pump.

Step 4 – Disconnect pump's connections

The top of the fuel pump assembly has three things connected to it: an electrical harness, and the feed as well as return lines. Pull the electrical harness off while depressing the plastic tab, then loosen the two clamps on the lines and pull them off. Mark the lines so you know which one goes where.

Figure 5. Remove harness.
Figure 6. Mark lines.
Figure 7. Remove lines.

Step 5 – Remove fuel pump's lock ring

Use your flat head screwdriver and place it on the ring on top of the fuel pump assembly, then gently hammer it with a rubber mallet counter-clockwise. Once it comes loose, which won't take much, remove it out of the way.

Figure 8. Hammer ring counter-clockwise.
Figure 9. Remove pump's ring.

Step 6 – Remove fuel pump

Pull the top part of the fuel pump off, then disconnect the two lines and electrical harness. Put the top part aside, then place two flat head screwdrivers in a crossed pattern from each side, place their tips on the two grooves of the pump's basket. Use the screwdrivers to turn the basket counter-clockwise, once it clicks out of place, pull it out with your hands. Disconnect the last electrical connection from the fuel pump.