2004 A4 3.0L Quattro Avant. Purchased used a few months ago from a guy that kept the car in excellent condition.

I believe I have something wrong with the fuel filter and/or fuel pump. It's making an humming noise whenever I step on the gas, BUT it only happens when my fuel tank is low.

I'm looking back at the service records I got from the guy I purchased the car from and on March 2009 (82,123 miles) there is a service record of exactly the same thing (loud humming noise) - the dealer replaced the fuel filter.

Then 3 months later June 2009 (84,223 miles) same thing, the previous owner had the same noise happen and the record says, "found an extremely noisy fuel pump, upon removal of fuel line, it broke, had to replace line. And they replaced the fuel filter (again. - not sure how necessary that was being it was just replaced 3 months ago)."

Now 2.5 years later, at 113k miles, it's back i guess. How come it keeps happening. Hope it's just the filter and not the pump. Pump and filter should last longer than 2.5 years and 28k miles shouldn't it?

Also, how come the humming noise only happens when i'm low on gas (1/8 tank or less)?

Thanks for any insight!

 

Replacing the filter will not help if the contaminants are present in the tank. Try replacing both the pump and the filter and clean the tank. Low gas will make these contaminants to vibrate which why I think you are more prone to the humming sound. (Not researched on this, completely predicting)

 

okay to my understanding they replaced the filter twice and a line going into the pump but never replaced the pum. I hate to say it but u probably need to replace your pump. Because eventually your pump will stop working and you will be stranded. Good news is the swap of the pump is very straight forward. Only took about 45 minutes to replace in my garage.

 

^^^^^
this

i suspect the noise you are hearing is the fuel pump. the reason you don't hear it when the tank has more fuel in it is that the fuel in the tank acts as a sound insulation.

pretty straight forward to replace

 

Thanks for the replies. Sorry, I was not clear, they also DID replace the fuel pump on the June 2009 service. I think I'll try to replace the filter first, and then if the noise is still there, I'll replace the pump.

Does anyone have a DIY how to change the fuel filter? 2004 A4 3.0L Quattro.

Thanks.

 

fuel filter is simple. Its located infront of the passenger side rear tire. Just pop ur head down there (thats what she said) infront of the tire look up and u will see a cover. follow the instructions. A word to the wise. First make sure u look at the filter before u buy a new one. There are two different types and i know mine had the 2 on eacch end. Some have one on one end and two on the other so this is important. Also when release the filter use needle nose pliers and press on the tabs to release. The method used in the diy wasnt easy but i found out needle nose makes this a whole whole lot easier. If u need any other help just post up. Or need pics to explain what im saying let me know. DIY: B6 A4 - Fuel Filter Replacement

 

Thanks for the instructions Pa4ul...I'll give it a go!

 

The noise is from the filter.......... 100% sure

The fuel pump doesn't make noise when its bad.... it just dies and won't start.

lol@ broken fuel line. Noobs...

 

I've had the same problem with my A4, but I had my filter replaced and it continued to make the same noise. I haven't replaced the fuel pump yet, but i'm always a little nervous its going to stop working when the tank gets low and it starts to whine. Guess I've been lucky so far. It was about 20K miles since I changed the filter. It whined even after installed a brand new filter. Do you think it could be the fuel pump? Or should I replace the filter again?

 

did you use an Audi filter or autozone...? Just like oil filters.... They are crap