K9Torro

Hello Guy's

Need some advice here, I have a 2001 Audi TT Quat. recently the primary fuel pump started making alot of noise from the passenger side rear seat area, Then the car started to exhibit fuel starvation problems.

I ordered a complete VDO/Siemens fuel pump assembly which included the pump, reservior/strainer and fuel sending unit all put together and ready to drop in. I also got a new rubber gasket.

I also replaced the fuel pump relay and fuel filter at the same time just to beon the safe side.

Prior to this the Fuel Gauge had always functioned normally.

I followed the instructions on the web and my Audi factory repair manual and the install of the new fuel pump, relay and filter went pretty smooth, all wires, hoses and the clip on piece were reattached to the new pump. I aligned the install arrow on the pump to the one on the tank. Put it all back together and car started and ran fine.

The fuel tank was just under half and the gauge seemed to read correctly.

NOW THE PROBLEM

I started the car to drive to work, got about 5 miles and got an audible tone warning and the low fuel symbol on my central display in the cluster when I checked the gauge it showed in the red near Empty.

I knew this was wrong but wanted to see what it would do so I filled it up at the next gas station it took about 7-8 gallons.

The gauge now read just under or right at 1/2 tank.

Came home after work, opened the tank the fuel was right to the top of the opening checked the movement of the sender arm which moved freely and seemed very loose. Reinstalled and no change.

Removed the new pump assembly and checked the wires to the sender, they seemed secure, I then removed the old sender unit from my pump and put it on the new pump and reinstalled it, thinking there might be a problem with the new sender ?

Now the gauge does not move from Empty at all and the low fuel warning dings and is showing the fuel pump symbol all the time in the display.

I un-hooked the battery and let the car sit to see if it would reset- no change

I pulled the fuses to the cluster and fuel pump, cycled the ignition switch and reinstalled the fuses - no change.

I am at a complete loss as to what the fark just happened, car runs great, starts right up no fuel starve problem.

Does anyone have any idea what to do next ???

Todd
S. Georgia USA

Eric Owen

It is likely to be a instrument pod issue.

The best way to test the fuel indication system that would be by use of the VAG-COM hex can usb dongle and software by Ross-Tech. If you plan on keeping your TT for a while, it would certainly be a good investment.

Eric Owen

I tried editing my reply but I was unsuccessful. My understanding is that there are two sensors. Did you replace both or just one? If not, that is something to consider.

K9Torro

Eric

I just replaced the primary pump assembly , so only the one sensor on the passenger side of the car , it is my understanding that to replace the other sensor you must purchase the whole assembly for the drivers side as they dont sell that one seperate, so another 205 dollars to test that theory.

I have had the car 5 years already

Thanks for the reply,

Todd

miamisam

Or another 10 bucks for a new drivers side seal replacement after you pull out the float resistor and clean it with a pencil eraser. Worth a try...
Lotsa good threads about that procedure here.

Audittblue

I had same issue after I did my fuel pump. What I did is took out the fuse for gauge cluster and fuel pump for 10min put them back in and it all went back to normal. I did this just the other day worked great for me

K9Torro

Hi Guy's

Thanks for all the replies.

I have already cleaned the contacts on the old sender with a red pencil eraser with negative results.

I have already pulled the cluster an pump fuses an attempted a reset wit negative results, I may try this again an add 10 minutes to the wait time as the first time I did it I did not allow any time, I have also removed the negative battery cable to reset with negative results.

One thing I have thought about I may have put the two clip on wires on the sensor board in opposite positions,, I nor Ced the small black plug only fits one way so they may be polarity specific I may pull it apart an reverse the position of these wires on the board an see what happens.

Any additional thoughts on this idea would help.

Todd
So. Georgia USA

Audittblue

Did you line up the arrow on the fuel pump to the tank one properly?

K9Torro

Yes, arrows are aligned.

Todd

Eric Owen

Do you have access to a VAG-COM dongle & notebook?
That is certainly where I would go with this next.