Originally Posted by SparTTan

Recently my fuel pump had been getting noisy -- I could hear it "groan" when pressurizing the fuel line before starting, and it was making an audible hum while sitting at idle. I figured this might be a sign that it was getting ready to fail. So rather than wait until it crapped out on me and left me stranded somewhere, I decided to take the proactive approach and replace it now. (I got a nice deal on a new OEM pump from Axey'rcat who was looking to get rid of a pump he bought but never installed.) Here's my how-to for the FAQ. (RoberTT also has a good set of pictures on his fotki that were a big help: <a href="http://public.fotki.com/RoberTT/maintenance/repairing_fuel_sender/">http://public.fotki.com/RoberTT/maintenance/repairing_fuel_sender/</a>)

Replacement is not too tough, but can be a stinky job since you are working with gasoline. Therefore the emptier your tank is, the easier this job will be. Obviously if your pump craps out on you don't have much of a choice - but if you do (as I did), try to run your tank down as empty as possible beforehand. Otherwise you may have to siphon some of the gas out.

Also, these instructions are for a quattro coupe. (I think the roadster requires the fuel tank to be lowered from underneath to access the pump...? Not sure.)

Step 1: Put out your cigarette.

Next, disconnect the negative ground of the battery -- I suppose this is optional, but probably a good idea since sparks are not preferred when working around gasoline.
<img src="http://img155.imageshack.us/img155/7568/img4608zx2.jpg">

Remove the rear seat bottom. It is held in by two clips, so just yank up on it sharply and it should unclip. (This is also a good time to vacuum out all the crap that has collected between the seatbacks and bottom.)
<img src="http://img250.imageshack.us/img250/5557/img4603sb4.jpg">

<img src="http://img254.imageshack.us/img254/2872/img4605nw9.jpg">

The quattro actually has two pumps: The secondary pump moves gas from the left side to the right, over the differential that sits under the middle of the tank. The primary pump is on the right (passenger) side. Unscrew the three screws holding the cover.
<img src="http://img201.imageshack.us/img201/527/img4609by0.jpg">

Pry off the electrical connector for the pump.
<img src="http://img166.imageshack.us/img166/7250/img4612nj1.jpg">


Remove the two hoses. They each have a button that presses in, which allows the connection to lift off. (Screwdriver tip is touching it in this pic.) Have a few rags ready, since supposedly these are under pressure, but my car had been sitting a while so nothing really came out when I pulled off the connectors.
<img src="http://img60.imageshack.us/img60/1285/img4613yj0.jpg">

Pay attention to the two arrows in this pic -- one on the pump and one on the fuel tank (where I wiped the dirt away). These need to be lined up when you put your new pump in.
<img src="http://img214.imageshack.us/img214/2228/img4615vm5.jpg">

Next remove the big threaded nut that holds the pump in. Audi has a special tool for this, but I placed a flat-bladed screwdriver on one of the lugs and tapped on it with a hammer, which rotated it off. The pump should pop up when the piece comes off.
<img src="http://img341.imageshack.us/img341/5493/img4617fl6.jpg">

<img src="http://img214.imageshack.us/img214/8505/img4619hj5.jpg">

Lift the top of the pump off and remove the rubber gasket.
<img src="http://img166.imageshack.us/img166/4430/img4622bu2.jpg">

Reach inside and disconnect the plug for secondary pump wiring harness. Disconnect the fuel line by pushing on the release button and sliding it off.
<img src="http://img155.imageshack.us/img155/8052/img4621xe4.jpg">

Next there is a plastic bracket that needs to be unhooked from the pump. It holds the secondary pump return hose. You have to reach pretty far in the tank to get at it, but it slides up and off the pump. You can see it on the right side of the pump in this shot.
<img src="http://img250.imageshack.us/img250/9160/img4624pn2.jpg">

Now you can work the pump out of the hole. Have a bucket ready to put the pump in, since it may still have gasoline in it that will leak all over. Make sure you use an official Audi bucket; no other bucket will work for this...
<img src="http://img155.imageshack.us/img155/1859/img4626xz3.jpg">

Feed your new pump into the hole and start reattaching everything, including the plastic bracket, the secondary pump hose, and the secondary pump wiring harness.
<img src="http://img254.imageshack.us/img254/8432/img4631za1.jpg">

Put on a new gasket. This gasket goes on the inside edge of the opening (which took a few minutes to figure out, since I didn't pay attention when I took it out).
<img src="http://img341.imageshack.us/img341/3836/img4634xp4.jpg">

Replace the top piece.
<img src="http://img254.imageshack.us/img254/2686/img4636ud5.jpg">

Replace your nut; tighten it up the same way you took it off. Make sure you line up the arrow on the pump with the arrow on the tank.
<img src="http://img254.imageshack.us/img254/4541/img4637yu0.jpg">

Snap on the connectors.
<img src="http://img214.imageshack.us/img214/333/img4638aw6.jpg">

Reattach and tighten the battery cable, turn on the ignition, cross your fingers, and try to start it. Mine didn't start right away -- had to crank for a while until it finally caught, which I assume was due to a dry pump that had to prime itself. Replace the cover, clean everything up and put the seat back in.

I was amazed at how quiet the new pump is. I guess my old one had been getting progressively louder but recently it was annoyingly loud. Now all I hear at idle is the low grumble of the Milltek -- much better!

Originally Posted by srebe

I posted a link on page 3 of this thread where some of the photos are located, but sadly not all.

For my part, this forum helped me diagnose the problem which was the right, main, pump float/sender. $140 part online. In the end I let my mechanic install it; mainly because I was concerned existing hoses may be brittle (after looking at what some old fuel pump hoses look like); and with connections to the secondary pump. Someday I would still like to try replacing the fuel pump(s), but with all new parts like you are doing.



The side without the dent :-)

Originally Posted by SparTTan

Hope it helps someone else someday...

Originally Posted by SparTTan

Recently my fuel pump had been getting noisy -- I could hear it "groan" when pressurizing the fuel line before starting, and it was making an audible hum while sitting at idle. I figured this might be a sign that it was getting ready to fail. So rather than wait until it crapped out on me and left me stranded somewhere, I decided to take the proactive approach and replace it now. (I got a nice deal on a new OEM pump from Axey'rcat who was looking to get rid of a pump he bought but never installed.) Here's my how-to for the FAQ. (RoberTT also has a good set of pictures on his fotki that were a big help: <a href="http://public.fotki.com/RoberTT/maintenance/repairing_fuel_sender/">http://public.fotki.com/RoberTT/maintenance/repairing_fuel_sender/</a>)

Replacement is not too tough, but can be a stinky job since you are working with gasoline. Therefore the emptier your tank is, the easier this job will be. Obviously if your pump craps out on you don't have much of a choice - but if you do (as I did), try to run your tank down as empty as possible beforehand. Otherwise you may have to siphon some of the gas out.

Also, these instructions are for a quattro coupe. (I think the roadster requires the fuel tank to be lowered from underneath to access the pump...? Not sure.)

Step 1: Put out your cigarette.

Next, disconnect the negative ground of the battery -- I suppose this is optional, but probably a good idea since sparks are not preferred when working around gasoline.
<img src="http://img155.imageshack.us/img155/7568/img4608zx2.jpg">

Remove the rear seat bottom. It is held in by two clips, so just yank up on it sharply and it should unclip. (This is also a good time to vacuum out all the crap that has collected between the seatbacks and bottom.)
<img src="http://img250.imageshack.us/img250/5557/img4603sb4.jpg">

<img src="http://img254.imageshack.us/img254/2872/img4605nw9.jpg">

The quattro actually has two pumps: The secondary pump moves gas from the left side to the right, over the differential that sits under the middle of the tank. The primary pump is on the right (passenger) side. Unscrew the three screws holding the cover.
<img src="http://img201.imageshack.us/img201/527/img4609by0.jpg">

Pry off the electrical connector for the pump.
<img src="http://img166.imageshack.us/img166/7250/img4612nj1.jpg">


Remove the two hoses. They each have a button that presses in, which allows the connection to lift off. (Screwdriver tip is touching it in this pic.) Have a few rags ready, since supposedly these are under pressure, but my car had been sitting a while so nothing really came out when I pulled off the connectors.
<img src="http://img60.imageshack.us/img60/1285/img4613yj0.jpg">

Pay attention to the two arrows in this pic -- one on the pump and one on the fuel tank (where I wiped the dirt away). These need to be lined up when you put your new pump in.
<img src="http://img214.imageshack.us/img214/2228/img4615vm5.jpg">

Next remove the big threaded nut that holds the pump in. Audi has a special tool for this, but I placed a flat-bladed screwdriver on one of the lugs and tapped on it with a hammer, which rotated it off. The pump should pop up when the piece comes off.
<img src="http://img341.imageshack.us/img341/5493/img4617fl6.jpg">

<img src="http://img214.imageshack.us/img214/8505/img4619hj5.jpg">

Lift the top of the pump off and remove the rubber gasket.
<img src="http://img166.imageshack.us/img166/4430/img4622bu2.jpg">

Reach inside and disconnect the plug for secondary pump wiring harness. Disconnect the fuel line by pushing on the release button and sliding it off.
<img src="http://img155.imageshack.us/img155/8052/img4621xe4.jpg">

Next there is a plastic bracket that needs to be unhooked from the pump. It holds the secondary pump return hose. You have to reach pretty far in the tank to get at it, but it slides up and off the pump. You can see it on the right side of the pump in this shot.
<img src="http://img250.imageshack.us/img250/9160/img4624pn2.jpg">

Now you can work the pump out of the hole. Have a bucket ready to put the pump in, since it may still have gasoline in it that will leak all over. Make sure you use an official Audi bucket; no other bucket will work for this...
<img src="http://img155.imageshack.us/img155/1859/img4626xz3.jpg">

Feed your new pump into the hole and start reattaching everything, including the plastic bracket, the secondary pump hose, and the secondary pump wiring harness.
<img src="http://img254.imageshack.us/img254/8432/img4631za1.jpg">

Put on a new gasket. This gasket goes on the inside edge of the opening (which took a few minutes to figure out, since I didn't pay attention when I took it out).
<img src="http://img341.imageshack.us/img341/3836/img4634xp4.jpg">

Replace the top piece.
<img src="http://img254.imageshack.us/img254/2686/img4636ud5.jpg">

Replace your nut; tighten it up the same way you took it off. Make sure you line up the arrow on the pump with the arrow on the tank.
<img src="http://img254.imageshack.us/img254/4541/img4637yu0.jpg">

Snap on the connectors.
<img src="http://img214.imageshack.us/img214/333/img4638aw6.jpg">

Reattach and tighten the battery cable, turn on the ignition, cross your fingers, and try to start it. Mine didn't start right away -- had to crank for a while until it finally caught, which I assume was due to a dry pump that had to prime itself. Replace the cover, clean everything up and put the seat back in.

I was amazed at how quiet the new pump is. I guess my old one had been getting progressively louder but recently it was annoyingly loud. Now all I hear at idle is the low grumble of the Milltek -- much better!