Help me ID Annoying Cabin Sound

mfeinst

So this has been present for a long time and I would like to get to the bottom of it. It sounds like a playing card being brushed on the spokes of a bicycle wheel. Video below. It happens when:

1. I press the throttle at a certain point, which can vary by gear, road, etc, but it almost always does it at some point.

At first I thought it was something vibrating at certain frequencies, but the noise occasionally happens right when...

2. I press the engine start button for a split second as the starter does its thing before the engine even starts up. This is less common but has ruled out a sound due to frequency.

Also, it doesn't happen when using SRM downshifting, which also helps disprove vibration and sound frequency as causes.

What mechanisms are common in our throttle and starter/ignition processes (but not synchro rev match) that could cause this?

Any help much appreciated.
https://youtu.be/TkYJz3yaNP0

EDIT: Replaced with YouTube link.

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DOOMMONKEY777

unbalanced drive shaft?
worn bushings?
u got tt in, turbos could be hitting the frame.

the vid loaded for like 5 sec then it does not load, something wrong with that site, drop it on you tube or something better.

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mfeinst

YouTube link posted.

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DOOMMONKEY777

It happends when you hit the gas, the engine vibration under load makes that sound, something is hitting something, get under the car and check if there are any marks btw turbos and the body, or maybe an exhaust n body or tranny.

You got to look guy, sound just says somthing is hitting something. At first i thought it was some baaaad engine knock, but i doubt it.

Like i sad could be bad bushing makes the engine twist and turbows hit the body. Just a guess here. GL OP.

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mfeinst

Sorry, I should clarify -- the noise is definitely coming from either behind the dash or under the hood.

Also, I have ruled out vibration since it happens quickly right before the motor turns over after hitting the start button.

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DOOMMONKEY777

U mean when it the engine twists to turn over to start, u hear that rattle?
Then one of these causes shuold be it.

Engine knock above 3k rpm,
Worn engine bushings, will give the engine huge play and cause turbos or w/e to hit the body,
Skipping gears, sound brings that to a thought, like the starter gears not being moved away from flywheel after engine start.

I cant think of anything else.

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mfeinst

Here, I managed to get an isolated video of just the click. It was really cold outside other morning and my car didn't want to start. After it stopped cranking, I was left with just that annoying sound. It's got to be something ignition related if it happens when the engine is off, no? What components are active during both startup cranking and acceleration?

https://youtu.be/yng5qNqi4Qw

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SouthArk370Z

Just going by the nature of the sound, my guess is that it's a door actuator somewhere in the HVAC system. But on modern, computer-controlled cars, it could be a lot of things.

Keep a paper towel core (or similar) handy and it may help you pinpoint the source next time it happens. Put one end to your ear and move the other end around until the sound is loudest.

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mfeinst

^Thanks for your input. Problem is that the video above is the only time I have ever gotten it to do that while I wasn't driving.

Edit: Okay, I found another video with the same issue. It must be a bad relay under the steering wheel somewhere.


http://youtu.be/Hg4zhDPuhlI
I'll look into it.

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zguynate

I was just about to say, it sounds electrical to me. A motor, an actuator, or a relay of some sort. Maybe steering lock? Have you done anything with that? Is the fuse pulled? Do you have one? Etc.

Im not saying thats it, just trying to throw out ideas.

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mfeinst

I have a 2012, so I don't think it's steering lock. Haven't done anything with it, but I'm going to look -- I found this diagram on a parts site, and this is exactly where the sounds seems to be coming from:



Looks like the reverse light relay and the heated seat (or HVAC-related) relay.

I'm trying to think which relays would only be active when the car is:

1. under load (usually moderate-heavy, but sometimes light) (i.e., not when revving in neutral or with syncrorev).

2. Turning the engine upon start ~ 30% of the time when starting the car.

Getting warmer, maybe....

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mfeinst

In case anyone cares, I found the source of the clicking.

It was the solenoid in my boost controller.

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old guy

Boost controller, as in Sprint Booster?

barncobob

sounded like electrical fuel pump but its in the back,,,a stethoscope would helped to pinpoint it.

mfeinst

Boost controller as in Electronic Boost Controller. I'm turboed.

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