Bad Fuel pump?

[blackcl]

My car died on me a couple of days ago and I think it might be my fuel pump. When I started it up I could hear a strange noise coming from that area that I've never heard before. drove it about 5Km and the car died on me. Right before that I noticed that when I hit the gas it sort of hesitated on me, like I lost power for a second.

I don't hear it priming anymore, and I tested the voltage on the pump with weird results ( between 1 and 2 volts when AC on and about 6 when cranking the engine). I know my battery is pretty old so that might explain the low voltage numbers? I tested for resistance and got 1ohm which I guess means my pump is still good... so is my filter bad? relay? What is my next step before I order a new pump.

Thanks guys

[Luxus Panzer]

Fuel pump is a wear item. If you buy one and it is not the problem, keep it for WHEN your pump dies.

[Let it snow]

You should have battery voltage (roughly 12 volts) between pin 1 and 4 at the pump assembly connection when cranking the engine. If you do not have the proper voltage the pump will not run.

[old guy]

Turn the key to the on position and check for pressure at the back of the fuel rail. Remove the black cap and depress the schrader valve. Have a rag handy. You should get a strong spurt of fuel.

[Luxus Panzer]

Turn the key to the on position and check for pressure at the back of the fuel rail. Remove the black cap and depress the schrader valve. Have a rag handy. You should get a strong spurt of fuel.

This...

Just be CAREFUL.

[blackcl]

Stupid question but is the valve itself covered by the black cap? I stuck a flathead in there and pressed on it but got nothing.

[customa4]

The cap is taken off in the picture above. You can see the threads where the cap would go right next to the red arrow. Pretty much just like a bicycle tube cap and a schrader valve on a bike. Same concept. Push the valve in and air will come out on a bike, in this case, gas should spray out. The valve is right on the other side of that red arrow.

[blackcl]

Ok, I did not get a spray. So far all signs lead to dead fuel pump? still curious why I'd be only getting about 6 volts while cranking... i'll test it again tomorrow.

[imnuts]

Have you checked the battery itself to see what the resting voltage is?

[blackcl]

Not yet, Will test tonight. Would a weak battery still be enough to start the car but while driving kill the power to the fuel pump?

[old guy]

No.

[charny]

Mine went around 145k and my relay was bad as well, used a off brand pump from ECS for around $200, no issues so far. Praise Audi for the access port underneath the rear seats.

[blackcl]

Checked my resting voltage on battery last night and came in at just above 11. Tried to check cranking voltage on fuel pump connector again and this time my car wouldn't even crank, the lights went all crazy with clicking noises. Sounds like my battery is toast. I've not been having the best luck with this car in the last 3 weeks.

[SJorge3442]

Mine went around 145k and my relay was bad as well, used a off brand pump from ECS for around $200, no issues so far. Praise Audi for the access port underneath the rear seats.

Ouch. $200 for a off brand pump? Europa has VDO (OEM) pumps for $185. Just did mine 2 weeks ago.

[diagnosticator]

Checked my resting voltage on battery last night and came in at just above 11. Tried to check cranking voltage on fuel pump connector again and this time my car wouldn't even crank, the lights went all crazy with clicking noises. Sounds like my battery is toast. I've not been having the best luck with this car in the last 3 weeks.

If the battery voltage is less than ~12.5 volts, the battery is completely discharged. 13.2 volts is fully charged, tested no load.

[B6a418t]

I have had my B6 for about 1.5 years. My pump went about 5 months ago or so. Basically I heard a "squishing" noise from the fuel filter area for a couple of days.. almost like the pump was having issues getting fuel into it. Was planning on swapping it out on the upcoming weekend. Then as I was driving the car just up and died. Replaced pump and filter (DIY, its an easy job) and it fired right up.

I had 275000 on what I can only assume was the OE pump, but the troubling thing was the inspection date on the filter.. 2001 :(

so safe to assume the car was not properly serviced in that department.

[blackcl]

Quick update. I was able to install the new pump and filter and the car is running again. Boy was it ever frustrating dealing those filter fuel line clips, it must have taken me a good couple of hours and a ton of bad words before I got all four off.
Hopefully this is the last of issues with the car for a while. I'm in about $2500 in repairs in the last month alone.

[Luxus Panzer]

Quick update. I was able to install the new pump and filter and the car is running again. Boy was it ever frustrating dealing those filter fuel line clips, it must have taken me a good couple of hours and a ton of bad words before I got all four off.
Hopefully this is the last of issues with the car for a while. I'm in about $2500 in repairs in the last month alone.

Fuel line clip hint for the future...


Compress them tighter before squeezing the clips to release ;)