I have engine light on and I checked on the computer and it says code P1476 , also I looked up for its meaning and it says:
EVAP Leak Detection Pump: Insufficient Vacuum.

BTW it is 2.8 quattro,

Please if anyone knows how to fix this problem , how to find a leak?

Thank you so much!

 

There is a vacuum diagram on the underside of the hood. Look at it and follow the lines for leaks.

 

ok I will follow the link, but how can I know where is the leak? should there be a sound or some indicator? I don't know anything about vacuum lines....

 

You may hear a hissing noise, but in most cases, you will see a tear/break in the line. Check the line from the back of the motor running to the left front wheel well. You should see a purge valve on the top of the air box. Follow that line to the rear of the car, and there is the EVAP purge canister at the rear of the car. Then there is another line from the canister to the leak detection pump. Check all those lines and connections. BTW did you recently get a tire damage on the right front wheel? I heard many cases where blown front tire damaging the vac line.

 

Yea I looked the diagram and I was confused it is kinda complicated....
no I have a tire damage of any kind. Yes I found the valve purge and it is making klicking noise , I heared that is normal. I checked with the audi dealer, vacuum Hose was replaced in 2006.
I was listening and I could hear very very quiet "pssss" sound on the right rear side... I don't know if that's normal. I would have to put the car on the lift to determine where is that coming form.

do you think that sound could be the leak?

 

The "Psss" sound could be a leak. And yes, you are correct on the purge valve clicking. It is normal. I would just trace the vacuum line to see if you can physically see any damage.

 

thank you for your advice but I will keep looking for the problem, cuz that "psss" sound could be the fuel pump... since it is on that side...

if you have any tips for me please let me know(like what is usually bad when vacuum system has a leak...etc.)

thanks

 

There really is no special way to find a leak other than tracing the line and checking all lines and connection.

 

Sometimes you can find a leak by spraying a little starter fluid on the vacuum lines while the motor is running. If the motor changes pitch (RPM) you can be sure your close to the leak.

Just be careful you don't blow yourself up cause the starter fluid can ignite if there is a spark nearby- so spray just a little at a time.

 

Yeah that is true if there is a leak in the engine compartment. Considering his problem is somewhere with in EVAP return system, it may not work.