99 Q45 buzzing noise in cabin

[dzznuts671]

ok first the car i have a 99 Q45t with about 125k on the speedo. all the regular maintenance have been kept up with. knock sensors,filters, reg oil change/transmission, brakes, etc. just today i have been getting a buzzing noise in the cabin. it kind of sounds like a card in a bicycle spoke just a little. There is no buzzing when the car is idling. However when i am driving the buzz is there and only gets faster and louder the faster i go. I tried rolling down the windows to see if it could be coming from the engine but i cant really hear anything. It sounds like it is coming from inside/behind the dash area. I cant seem to pinpoint exactly where the sound is coming from. i am going to turn my car in to my mechanic but would like to know what it could possibly be before i turn it in. I have tried diff searches but to no avail. Any help would greatly be appreciated. Thank you in advance!

[BadQ45t]

Is it coming from the back perhaps by the gas tank. I know first gen people have big time buzzing noise from their failing fuel pumps. I have not heard of that yet in 2nd Gens but our time could be here.

Where do you think the buzzing is coming from, at least isolate that.

[dzznuts671]

no it doesn't sound like its coming from the rear/fuel pump. actually it sounds like its coming from under the shifter area. im hoping its nothing transmission related. transmission fluid is fine/topped off. I use eneos for my fluids. bout that time for my once a year transmission fluid change. Flushed my transmission and changed the filter about 2yrs ago. Change the fluid once a year.

*thanks BadQ45 for the help

[loystock]

Cabin buzzing noise is typically associated with failing fuel pump. But noise from the shifter area...strange. You may have to pop the hood and/or safely jack up the car to locate source of noise. Use a mechanic's stethoscope or improvise with a long screw driver (just don't touch moving parts). Maybe it has to do with idler pulley, AC clutch but hopefully not the transmission...could be expensive.

[dzznuts671]

Thanks loystock will look into that. Hopefully its not the transmission!

[Lokim]

Shift lock solenoid?

[dzznuts671]

found the culprit! it is the rubber coupling thats on the first part of the drive shaft. UUGGGHH!! The rubber was falling apart and rubbing the inside wall making the noise. and they dont sell that piece by itself. Went ahead an got a brand new drive shaft. Will update when everything gets put back together!!! SUCKS!!

[BadQ45t]

That sucks, how much does did that set you back?

[dzznuts671]

in the shop now but they quoted me about $800 installed. i checked on IOS and the part looks to run about $680 - $700. Hopefully i will be getting it back this week. Thanks everyone for the help. Will update with the final outcome and test drive.

[dzznuts671]

got the car back. Runs like a champ now. no noise. forgot to take a picture but the rubber bushing/dampner thing in the drive shaft joint was worn out. It looked like a blown tire with wires and rubber sticking out. Thats what was making the noise when it was hitting against the drive shaft tunnel. Cost me almost 700 for the drive shaft and about 150 labor. They only sell the whole drive shaft. Next on the list is the inner/outer tie rods and tension rods. Next time your under your car i would recommend checking your drive shaft.