View Full Version : Name That Noise!!!
LocoLobo
03-20-2019, 03:06 PM
I noticed yesterday that my 2011 S4 with around, 135k miles, has formed a very odd sound. I thought that it sounded like it was coming from the timing chain tensioner due to the number of post about the "chatter" those cause over time. This isn't exactly a chatter.
--> The noise doesn't sound like metal on metal, sort of a "purring" sound if I had to describe it. It's loud on the back of the engine near the timing cover, but even louder under the car, closer to the starter.
--> As you depress the gas it becomes obvious and as you let off the gas it trails off.
--> I haven't noticed a loss in power.
--> I removed the serpentine belt to see if removing the alt, PSP, AC would affect it and it didn't.
--> Can't hear while I'm driving due to my exhaust....
https://youtu.be/BkD6diXcj6c
What are your thoughts? Please help!
Solarsuplex
03-20-2019, 04:19 PM
part of me wants to say its the starter....
fstr n u
03-21-2019, 03:54 PM
sounds mechanical for sure....could be starter. try misting water over the area as you rev and see if the water molecules move...if so it's something else.
LocoLobo
03-21-2019, 06:26 PM
yeah, I was leaning toward the starter.
fstr, I'm not quite sure what you mean by misting water over the area.
fstr n u
03-21-2019, 08:11 PM
if you have a leak with any pressure, use a spray bottle with water and spray over the area...if the water mist is moving around or bubbling, it'll help steer you towards a leak or other
Apologies...i've had an evening full of bevvies (Crown Royal and Coke). I've been working on boosted motors for a long time (10 years) and we use a series of tricks to problem solve weird noises, leaks and others....
proxemus
03-21-2019, 09:49 PM
bull frog, u got a bullfrog somewere underthere... it almost sounds like a fan hitting something or chain rubbing
if you have a leak with any pressure, use a spray bottle with water and spray over the area...if the water mist is moving around or bubbling, it'll help steer you towards a leak or other
Apologies...i've had an evening full of bevvies (Crown Royal and Coke). I've been working on boosted motors for a long time (10 years) and we use a series of tricks to problem solve weird noises, leaks and others....
Crown royal... you from manitoba?? lol
Big_Joe
03-22-2019, 02:45 PM
I doubt it will be the starter, the starter solenoid engages a gear out of the starter and spins the flywheel, you would be hearing it while the car is idling and it would be more a whining metallic sound
If you have your belt still off run the car and check if the voltage drops, because it should be if the alternator is not turning, if it doesn't drop then there is a possibility of the starter being stuck out and generating electricity from running on the fly wheel. just turn off everything you can that would use power.
Did you remove the supercharger belt as well? it sounds like some sort of bearing failure, to me any how.