Help weird noise when Heat is on

[201]

Hello friends,
I need some help!! When my car is warmed up and heater is on I hear like a tapping water drop noise not coming from the vents but seems like under me? If that makes sense. My car just hit 55k miles so my warranty has expired..(yes I know I should have gotten extended warranty) but I had no problems whatsoever till now

[HJ]

Im by no means a car expert. But you should maybe try turning on the AC see if water drips from under the car. If nothing drops It could have something to do with the ac pan/tray flooding.

[turboawd]

While stationary?

[201]

Originally Posted by JSN

Im by no means a car expert. But you should maybe try turning on the AC see if water drips from under the car. If nothing drops It could have something to do with the ac pan/tray flooding.

Hmm..I will try turning on the AC

[201]

Originally Posted by turboawd

While stationary?

Well the noise is most noticable while stationary, I really cant tell while im driving because the car gets a bit noisy.

[turboawd]

Noise with heat on engine off?

[201]

Originally Posted by turboawd

Noise with heat on engine off?

When the engine is on while stationary the sound gets a bit louder and clearer.
When the engine is off with heater on the sound kinda fades but you can still hear it

[201]

this sound only comes when the heater/ac is on.
when its off with engine turned on or off it goes away completly

[turboawd]

Sounds like a minor issue.

[201]

Ok so I ended up getting extended warranty mainly for this issue and for future problems. I took it to my local BMW dealer which I wont name yet but it has been a fustrating experience. Ive gave them specifics by detail on how you could hear the sound for example closed windows , radio off and most importantly keep the engine running for atleast 10+ minutes with the climate control on because it doesnt make the noise right away it seems like the engine needs to be warmed up and seems as if something builds up then has no choice but to start making the water drop sound. I check under the car there is no leaks coming from under the car but you can definatly hear it interally in the car that something is hitting metal. The water drop sound isnt fast theres about 2-3 seconds of quietness in between before you the drop. Im afraid if this is indeed water hitting something internally it might rust or flood under my passenger site floor. The BMW dealer has no clue says they cant tell where the noise is coming from and hear nothing. I volunteered to go back to the dealer and pinpoint the noise. Instead they tell me its fine they will try to find it. 10 days has passed I call for an update only for them to tell me once again the "engineer" cannot duplicate the sound. Ive been hearing this drop sound for over a month everytime when the climate control is on so theres no away it just randomly goes away. If I turn off the climate control the drop sound is completely gone. I cant ask them to check a certain area because I have no idea where its coming from. But as an engineer wouldnt there be certain areas where they would look knowing it has to do with climate control issues. Anyone have advice?

[TOPEC]

does it happen when the car is wet, after sitting in the rain?
do u have the sun roof shade open or closed?
and does the tapping sound increase along with the climate control fan speed increase?
and if u open the windows when the tapping noise is happening, does it stop?

[201]

Originally Posted by TOPEC

does it happen when the car is wet, after sitting in the rain?
do u have the sun roof shade open or closed?
and does the tapping sound increase along with the climate control fan speed increase?
and if u open the windows when the tapping noise is happening, does it stop?

Yes I hear it when its dry outside and also when it rains as well but with everything closed. The noise is kinda faint but solid? if that makes sense. I can hear it with the windows open while im stationary without much outside noise. You can still hear it when you increase the fan speed from 1 2 3 4 bars but after that it gets too noisy for me to hear the drop sound. Best way I can describe the sound is when a kitchen sink is not fully turned off water dropping slowly from the faucet onto the metal bottom which this case would be a clearer sound. The sound im getting is very similiar but it sounds more concealed. Thing is I hear this only when im stopped. When im driving I cant hear it, hard to tell if it goes away when moving. It's weird because when Im stopped you clearly hear it , but as soon as I turn off the climate control the sound completly goes away , there is no after effect of the noise getting smaller it just goes away.

[TOPEC]

does it sound like this at all?

[201]

Originally Posted by TOPEC

does it sound like this at all?

Nope the drops arent that fast. Its more like "drop" pause 1 2 3 seconds then "drop" pause 1 2 3 over and over. It just fustrating on the dealer part of this because they just give me a shortned answer that they hear nothing. I first waited a week then called in for an update only to have the SA tell me they dont know where its coming from. I told them I would come in right away to help locate the noise but they said no its fine. Now I get a call from them day before yesterday (this is now 10 days passed ) telling me I should come in to help find noise, so I said I would come in yesterday they said no the tech isnt available. So now there off today tomorrow and tuesday for holidays so I have to wait till wednesday. I mean why take 10 days to tell me they cant find it then take another few days to tell me to come in. If I go on wednesday and pin point it out Im pretty sure itll take them another 10 days to give me another excuse that they dont know where it's coming from. They have literally no idea where to start to look for the problem when its climate control related. When I had a few indy mechanics I know sit in my car and hear the noise they suggested alot of things like maybe leaves and debris blocking an exit point, climate rotor not working properly , another member here on this thread mentioning something with the pan tray over flooding due to bad lubing all good points but dealer seems to have no suggestions nor will they check anything as of yet.

[TOPEC]

my dealer couldnt replicate the noise either, been living with it ever since. didnt want them to start tearing apart the car.

[201]

Originally Posted by TOPEC

my dealer couldnt replicate the noise either, been living with it ever since. didnt want them to start tearing apart the car.

If it was some random squeaking noise I wouldnt be this worried. Just the fact that it seems as if water is discharging somewhere inside the car is what that worries me. At first I thought it really had something to do with leaves and debris because the area I live in has tremendous amount leaves falling. A few times I had to open my hood and get leaves out of the top area right under the windshield. Some of the leaves seemed to have fallen into an opening right under the bottom of the windshield. I had to stick my arm in the tight opening when engine is cold to take out leaves from the bottom part as well. Idk I explained this to my dealer as well they havent checked up on it.

[TheUltimateDrivingManiac]

I have the same issue and had it from the beginning. Always forget to report it to the SA.

[turboawd]

Originally Posted by TOPEC

does it sound like this at all?

did you see that water bubble at around 19 second mark? i'm wondering if your sunroof drains are plugged or something weird. the hvac is slightly pressurizing the cab...
does the sound go away when you open a window?

[turboawd]

Originally Posted by dinanF16

If it was some random squeaking noise I wouldnt be this worried. Just the fact that it seems as if water is discharging somewhere inside the car is what that worries me. At first I thought it really had something to do with leaves and debris because the area I live in has tremendous amount leaves falling. A few times I had to open my hood and get leaves out of the top area right under the windshield. Some of the leaves seemed to have fallen into an opening right under the bottom of the windshield. I had to stick my arm in the tight opening when engine is cold to take out leaves from the bottom part as well. Idk I explained this to my dealer as well they havent checked up on it.

have you tried laying on your garage floor with fan on and engine off to hear the noise underneath?

[201]

Originally Posted by turboawd

have you tried laying on your garage floor with fan on and engine off to hear the noise underneath?

I actually never thought about that.. Will be the first thing I suggest to them once the dealer opens within the next few days thanks!

[201]

Originally Posted by TheUltimateDrivingManiac

I have the same issue and had it from the beginning. Always forget to report it to the SA.

Interesting, Does turning your ac make water drip under the car like how it should? Even with my ac blasted full I have no drips from under my car either, might sound like a dumb question but is it because its cold or can this be part of my problem as well

[TOPEC]

Originally Posted by turboawd

did you see that water bubble at around 19 second mark? i'm wondering if your sunroof drains are plugged or something weird. the hvac is slightly pressurizing the cab...
does the sound go away when you open a window?

yes i see the drip, and yes opening the windows stops the noise, and yes i know it has to do with the drains and cabin pressurization. no the dealer "could not" replicate the problem, so instead of them tearing apart my car, i rather them not and just leave this be. the drains are not plugged, i've poured water into the sunroof "gutters" and it does drain. if u check my thread i've documented this whole problem and few others r having similar issues.

https://f15.bimmerpost.com/forums/sh....php?t=1306131

and just a note, no sunroof seal forms a completely water tight seal, it just prevents water from leaking in at a rapid rate. it is to slow the leak to a drip so it drips into the drain channels and into the drain hole.