: Hi from new member



RichF
10-01-11, 05:42 PM
Hi All:

My wife and I just bought a 2012 CTS-V sedan. Have about 600 miles on the car now. Performance is awesome. It's our first Caddy, and our first supercharged car. We are also Corvette enthusiasts. Anyway, I heard a rattle from under the hood from day one. Hadn't spoken to the dealer yet.... Today I determined that it's the supercharger pulley or isolator, I guess. Thanks to this forum, I see I'm not losing my mind, and got some good info. I was concerned because we are planning to drive to South Carolina from NY in a couple of weeks, and don't want the thing to blow to bits on the way. I guess it's "normal" ? Thanks, everybody :-)

Rich F

MReiland
10-01-11, 06:28 PM
Depends on how loud it is, it may actually be normal. The TSB that the dealer has on it will determine if they need to change anything, most likely it is normal if you can only hear it from outside the car or with the hood up at idle.


Ohhhh. And WELCOME!

smackdownCTSV
10-01-11, 06:32 PM
PIP4523C: Marble Type rattle Noise At Idle From The Supercharger - Potential Noise Characteristic - (Jan 26, 2011)

Subject: Marble Type Rattle Noise at Idle from the Supercharger - Potential Noise Characteristic Subject: Marble Type Rattle Noise at Idle from the Supercharger - Potential Noise Characteristic


Models: 2009-2011 Cadillac CTS-V Models: 2009-2011 Cadillac CTS-V

2009-2011 Chevrolet ZR1 Corvette 2009-2011 Chevrolet ZR1 Corvette

with 6.2L Supercharged Engine (RPO LS9 or LSA) with 6.2L Supercharged Engine (RPO LS9 or LSA)

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This PI was superseded to update model years. Please discard PIP4523B. This PI was superseded to update model years. Please discard PIP4523B.


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The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI. The following diagnosis might be helpful if the vehicle exhibits the symptom (s) described in this PI.

Condition/Concern: Condition / Concern:
A supercharger noise may be experienced at idle that sounds like marbles rolling around in the supercharger. Some may also describe this as an erratic rattle-type noise that sounds similar to combustion noise on a diesel engine. A supercharger noise may be experienced at idle that sounds like marbles rolling around in the supercharger. Some may also describe this as an erratic rattle-type noise that sounds similar to combustion noise on a diesel engine.

This noise will only be heard at idle and it will go away when the RPM is raised off of idle slightly. Typically, the hood will have to be open to hear the noise outside of the vehicle or the vehicle will have to be parked next to a wall (ie...restaurant drive-thru, etc) to hear it from inside the passenger compartment. This noise will only be heard at idle and it will go away when the RPM is raised off of idle slightly. Typically, the hood will have to be open to hear the noise outside of the vehicle or the vehicle will have to be parked next to a wall (ie. .. restaurant drive-thru, etc) to hear it from inside the passenger compartment.

When comparing this noise to other vehicles, it may be noted that other vehicles exhibit the same noise at idle but some are louder/quieter than others. When comparing this noise to other vehicles, it may be noted that other vehicles exhibit the same noise at idle but some are louder / quieter than others.

This noise may be mistaken for a bad supercharger bearing, which may lead to unnecessary supercharger replacement, but it is most likely a normal noise characteristic of the torsional isolator at idle. This noise may be mistaken for a bad supercharger bearing, which may lead to unnecessary supercharger replacement, but it is most likely a normal noise characteristic of the torsional isolator at idle.

Recommendation/Instructions: Recommendation / Instructions:
If the noise above is experienced, perform the diagnostic steps below: If the noise above is experienced, perform the diagnostic steps below:

•Park in an open area with the hood and windows closed. • Park in an open area with the hood and windows closed.
•With the engine at operating temperature, raise the RPM to 1200 RPM and re-evaluate the noise while sitting inside of the vehicle. • With the engine at operating temperature, raise the RPM to 1200 RPM and re-evaluate the noise while sitting inside of the vehicle.
If the noise is no longer present, this should be considered a normal noise characteristic of the supercharger - do not replace the supercharger in an attempt to repair this noise. If the noise is no longer present, this should be considered a normal noise characteristic of the supercharger - do not replace the supercharger in an attempt to repair this noise.

If the noise is still present, allow the engine to cool, temporarily remove the supercharger belt, and listen to the noise again. If the noise was present at 1200 RPM with the belt on but is gone with the supercharger belt removed, replace the supercharger by following SI procedures and re-evaluate the concern. If the noise is still present, allow the engine to cool, temporarily remove the supercharger belt, and listen to the noise again. If the noise was present at 1200 RPM with the belt on but is gone with the supercharger belt removed, replace the supercharger by following SI procedures and re-evaluate the concern.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

RichF
10-01-11, 07:24 PM
Thanks! :)

JOEYCTS-V
10-01-11, 07:43 PM
Where in NY are you? Congrats on the car.

adrian-s
10-01-11, 10:10 PM
Congrats on the new car!

-adrian

Mikevette
10-02-11, 10:58 AM
welcome to the brother hood enjoy miles of smiles and thumbs up from on lookers.

Mike P.

JimmyH
10-02-11, 09:21 PM
Congrats and welcome to the forums :thumbsup:

lipps
10-14-11, 12:14 AM
Hi Rich, I just been searching the same issue as you and decided to join this cadillac forum since a lot of us have been having the same issue as you. Looks like it is normal at a idol but still bugs me a bit cus its a rattle noise.
My brother installed a TRD supercharger on his tundra (TRD hehehe poor fella) and he I was talking to him about the slight rattle noise and he also thought something was wrong with mine. He then said in his instructions that a rattle noise at idol is normal and the TRD is a Eaton supercharger just like the CTS V.
So just enjoy your drive to South Carolina wish I was more south its feels like snows coming up here in Alberta Canada

Thanks Jason

RichF
10-15-11, 06:14 AM
OK - Thanks for the input !