Ckroush

I tried searching for this problem but didn't exactly know what to search.
Here's my problem: When I start the car, I hear this EXTREMELY loud buzzing noise coming from somewhere beyond the dash.

It sounds like an old prop-engine plane about to take off and it's very loud (no exaggeration). It sounds like I'm riding in a P-51 Mustang.

The noise goes away after about 15 seconds but it happens every single time I start the engine. It just started making the noise today.

deejay

iTrader: (2)

i notice the same noise every time i start my car, but it is very faint. you can only tell if you are listening for it.

sorry I can't be of more help, it just seems the noise is normal like the headlight adjusters when accellerating, but something is wrong if it is super-amplified.

Ckroush

I just pulled into a vacant parking lot and did some investigative work. It also makes the noise when just the ignition is on.

The sound cannot be heard outside of the car. Also, when I press the brake pedal down, the pitch drops and the buzzing sounds deeper. When I release the pedal, it resumes as normal. It does it's 15-20 second noise and then goes away. It's not Boeing commercial jet loud, but it's definately not faint.

What the hell is this?

UncleRay

iTrader: (2)

I'm guessing alternator? Serpentine belt? Timing belt?

bg_281

I have this same problem!!! When I used to have my honda I got into a minor accident and the headlight got pushed back into the abs pump... eversince that day I had that buzzing noise in my car... and since that part was about 1500 bucks I just disconnected it. So when I start my gs with the hood open and I listen around the brake resovoir I hear the same noise... I dont know if thats what it is but it seems like both cars had the same problem...

Ckroush

My problem is a little different though because it can't be heard from outside the car and I haven't been an an accident. I really hope it's not the abs pump though

Debonair

Sounds like maybe a relay gone bad. put your ear near the fuse boxes and see if it is louder there.

oohpapi44

iTrader: (1)

I've got the same thing but it's not constant, I'm thinking it's the AC servo behind the dash that's starting to fail. It's a buzzing noise like gears are spinning but a belt is slipping. It's definitely not engine related, more like a remote control car motor spinning rapidly. I can't get the problem to recreate itself whenever I'm around my mechanic so he has no idea what I'm talking about when I mention the sound.

Ckroush

I'll definately see if I can hear it around the fuse box, but it sounds like it's right behind the center of the dash. I don't know if it's anything A/C related because it makes the sound regardless of the A/C being on or off.

It DOES sound like a small motor. Like the Red Baron is flying over my head.

oohpapi44

iTrader: (1)

Mine too, I turn off the a/c whenever I hear the sound and it still goes on. I agree that it's coming directly from the middle of the dash. Gets pretty loud then the rpms will drop. It sounds like a small motor and like a belt is slipping (on mine since it's not constant), or slipped (on yours since it is). But it's similiar in that it does go away, although mine has lasted for a full 45 seconds. It only happened to me once last month but I have had it happen as frequently as 4 times in a day (and I can already be in motion when it kick in)

I kinda want whatever it is to fully break so I can take it to my mechanic and he can take a look at it. I've been alone when it's happened so far but it would be pretty embarrassing to explain it away when I've got company

Hectorm

I think is possible the starter keep running after the car start? or could be ABS brake pump keep running?
Could you use a short rubber hose to located the noise?

ElitistK

iTrader: (4)

it does not happen everytime you start the engine, but everytime your key turns into ignition.

it's your servo motor, the one that mixes hot and cold air together. If you're missing hot air on one side of the car, then it's the servo motor for sure.

do another search. this topic has already been covered.

Debonair

I believe this part is located behind the glove box near the blower motor and cabin air filter. Open up the glove box and see if its louder in there.

gs-ireland

Check your ABS pump! What may be happening is when you pump the pedal, you are pushing fluid against the pump, hence the tone change! The pump will normally activate for 5-30 secs, depending on how much air is in your brake system.

The ABS pump does not operate everytime if the ABS pressure reservoir is still pressurized eg: if you turned the engine off for 1-2 mins . It will activate after the engine was off for at least 10-30 mins

swat1727

iTrader: (2)

yeah most likely ur abs. i have the same problem with my honda, but dont know how to fix it. =(