High-pitched whining sounds at engine start and when driving
Hello all.
I'm a new owner of a 2005 A4 1.8T (B6 model) automatic, sport package with 61,000 miles for all of about 3 days, but there is a sound I've been trying to diagnose.
Half the time, there is a high-pitched whining/whirring sound that seems to originate from the rear of the car and may even sound louder inside the cabin. It is most noticeable when driving slowly, but only because there are less ambient sounds: it seems that the volume or pitch are unaffected by RPMs, velocity, or anything I do.
I did the service check and everything's OK and before I bought the car, I had it checked by an Audi mechanic for a pre-purchase inspection and it passed with flying colors.
Today, specifically, I didn't hear the sound in my first trip in the car (I live in LA and we were in the high 60s to 70s today, by the way), but I heard it when I went to my next destinations.
I also noticed today that I hear the same whine for all of 1-2 seconds as I turn the key in the ignition to ON, but it quits the moment the dashboard lights up.
After a few hours of rest, I can still hear the whine during that brief interval between during the key and having the dash light up, but not while the car was idling.
I've searched far and wide and the only set of symptoms that seem to match was referred in http://www.fixya.com/cars/t847601-high_pitched_noise , and the only response was from somebody for whom the problem went away when a fan that had chips on the blades was replaced, but in these forums, I see that the fuel line is often blamed for sound from the rear/underside of the car.
I'm planning on having the dealer I bought it from take a look (it was off a GMC lot and came with 3 mo/3k warranty for parts and service), but I probably won't trust them 100% since they may not know Audi's particularly well.
I would appreciate and advice (and hopefully reassurance that I didn't just buy a fuel pump issue--the car is running fantastically).
Thanks again,
Cisco
I'm a new owner of a 2005 A4 1.8T (B6 model) automatic, sport package with 61,000 miles for all of about 3 days, but there is a sound I've been trying to diagnose.
Half the time, there is a high-pitched whining/whirring sound that seems to originate from the rear of the car and may even sound louder inside the cabin. It is most noticeable when driving slowly, but only because there are less ambient sounds: it seems that the volume or pitch are unaffected by RPMs, velocity, or anything I do.
I did the service check and everything's OK and before I bought the car, I had it checked by an Audi mechanic for a pre-purchase inspection and it passed with flying colors.
Today, specifically, I didn't hear the sound in my first trip in the car (I live in LA and we were in the high 60s to 70s today, by the way), but I heard it when I went to my next destinations.
I also noticed today that I hear the same whine for all of 1-2 seconds as I turn the key in the ignition to ON, but it quits the moment the dashboard lights up.
After a few hours of rest, I can still hear the whine during that brief interval between during the key and having the dash light up, but not while the car was idling.
I've searched far and wide and the only set of symptoms that seem to match was referred in http://www.fixya.com/cars/t847601-high_pitched_noise , and the only response was from somebody for whom the problem went away when a fan that had chips on the blades was replaced, but in these forums, I see that the fuel line is often blamed for sound from the rear/underside of the car.
I'm planning on having the dealer I bought it from take a look (it was off a GMC lot and came with 3 mo/3k warranty for parts and service), but I probably won't trust them 100% since they may not know Audi's particularly well.
I would appreciate and advice (and hopefully reassurance that I didn't just buy a fuel pump issue--the car is running fantastically).
Thanks again,
Cisco
Electric fuel pump in the gas tank. They are usually quiet... but it may be going out.
Open your gas filler door and remove the gas cap. Have someone move the key to "on", and if you hear the whir or whine coming from inside the gas tank, then presto, you have your answer.
Open your gas filler door and remove the gas cap. Have someone move the key to "on", and if you hear the whir or whine coming from inside the gas tank, then presto, you have your answer.
No solution, yet, but honestly, I haven't really had the chance to take the car to the mechanic. I didn't hear the sound coming from the gas tank and my fluids are good (easy stuff to check).
I've realized that the sound comes on more when the car is warmed up, tends to decrease when coasting, but increases again when either idling with the brake on or with any acceleration (more acceleration does not cause more sound--may even be softer with speed).
More later.
I've realized that the sound comes on more when the car is warmed up, tends to decrease when coasting, but increases again when either idling with the brake on or with any acceleration (more acceleration does not cause more sound--may even be softer with speed).
More later.
SOLVED!
Thanks for the advice (not just in this thread, but from lurking in the forums in general). Admittedly, the listen to the gas cap thing didn't seem to work, but it was the fuel pump. I first had the filter replaced in the hopes that the cheaper repair would work and it took care of 75% of the noise, but the fear of being left on the side of the road made me go ahead and replace the pump, too. The sounds are entirely gone.
Thanks again,
Thanks for the advice (not just in this thread, but from lurking in the forums in general). Admittedly, the listen to the gas cap thing didn't seem to work, but it was the fuel pump. I first had the filter replaced in the hopes that the cheaper repair would work and it took care of 75% of the noise, but the fear of being left on the side of the road made me go ahead and replace the pump, too. The sounds are entirely gone.
Thanks again,
Well, I didn't solve it alone. The mechanic at Audi listened to it for 1 second and knew: replacement solved the problem. Everything I read here made me feel confident (almost like a second opinion). There really is no other motor that should be in the back where the fuel tank is.
At the dealer (Rusnak in Pasadena, CA), it cost under $700, parts and labor. Not too cheap, but better than getting stuck at the side of the road (if the fuel pump fails, it can do it suddenly: happened to my wife twice in her Camaro).
At the dealer (Rusnak in Pasadena, CA), it cost under $700, parts and labor. Not too cheap, but better than getting stuck at the side of the road (if the fuel pump fails, it can do it suddenly: happened to my wife twice in her Camaro).


