Diagnosis help
Thread Starter
Senior Member
Joined: Nov 2013
Posts: 323
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From: Los Angeles, CA. USA
2013 c250
Diagnosis help
Engine mounts or alternator pulley?
When I'm backing up it chirps and when turning while backing up, vibrations. No trouble while driving, no problem when idling, only time is in the morning when I'm backing her out, slowly b/c there's a tree near my garage. It would happen every time I back up, but when I go in reverse usually I go a bit faster which takes away these sounds.
When I'm backing up it chirps and when turning while backing up, vibrations. No trouble while driving, no problem when idling, only time is in the morning when I'm backing her out, slowly b/c there's a tree near my garage. It would happen every time I back up, but when I go in reverse usually I go a bit faster which takes away these sounds.
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Joined: Sep 2011
Posts: 1,657
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From: Austin, TX
2005 C230K(sold), Mk7 Jetta
If in doubt, take the belt off and check the alt pulley.
Grab it with your hand and try to quickly rock it clockwise/counterclockwise.
One way it should freewheel while the alternator core continues spinning the other way.
With the belt off, you could also start the car and quickly test if it still chirps in reverse etc (don't overheat it since the belt drives the water pump).
I am not sure as to how the motor mounts could be chirping
Grab it with your hand and try to quickly rock it clockwise/counterclockwise.
One way it should freewheel while the alternator core continues spinning the other way.
With the belt off, you could also start the car and quickly test if it still chirps in reverse etc (don't overheat it since the belt drives the water pump).
I am not sure as to how the motor mounts could be chirping
Last edited by VVF; Jun 26, 2014 at 04:29 PM.
