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Discussion Starter · #1 ·
Car just broke 119k, very well maintained.. I currently have an out Exhaust CPS sensor that is getting replaced on Tuesday. Since I've had the car, I've always noticed a very faint sound that almost sounds like marble's in a jar. Anyone have experience this before? I'll try and take a video sound this afternoon and post if I can, but it's such a faint sound, I'm not sure if the camera will even pick it up...
 

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Could be a socket that a mechanic dropped and is rolling around in the belly pan.
 

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Could be a socket that a mechanic dropped and is rolling around in the belly pan.
thats funny...

OP - - I think you need to share more f a c t s -that would help / when/where/engine rpm/speed/etc etc etc...

...sure it's not the vanos?
 

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Car just broke 119k, very well maintained.. I currently have an out Exhaust CPS sensor that is getting replaced on Tuesday. Since I've had the car, I've always noticed a very faint sound that almost sounds like marble's in a jar. Anyone have experience this before? I'll try and take a video sound this afternoon and post if I can, but it's such a faint sound, I'm not sure if the camera will even pick it up...
Does the sound resemble marbles in a JAR (as in glass) or a CAN?
Marbles in a can is the fateful sound of engine knock and/or the car running too lean on turbo charged cars...I don't know if this is the case for the M5 but the description of the sound is a good indicator.

Do you hear it more when you are driving close to a low wall or an island with brush that reflects sound? I hear it myself from time to time, and mine sounds like what the other fellow poster had said - Vanos.

What gas do you use? You might want to try switching gas and I assume you are using 91 octane at least right?
 

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I have had the exact same problem though not in the M5. It was due to the timing of the car being too advanced which led to the car pinging/knocking. It was more noticible when the engine was under a heavier loads such as driving up hills, high temp situations and under heavy throttle situations. It was very faint as well though the noise would be more pronounced under the situations I mentioned above. Once I retared the timing back a bit the noise was gone.

I am not sure how one goes about checking the timing chain on the M5 but I would give that a shot because "marbles in a jar/can" is most often associated to timing issues from my experience.

Good Luck.
 

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I am not sure how one goes about checking the timing chain on the M5 but I would give that a shot because "marbles in a jar/can" is most often associated to timing issues from my experience.
Or Bad/Cheap gas...:crying2:
 

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I highly doubt it is ignition knock. This car has very efficiant knock sensors and will pull timing way before you can or will hear audible knock as long as premium fuel is used. i am also sure he would be getting an SES or codes if he had audible ignition knock

Op do you have any loss of performance?


Ryan


Does the sound resemble marbles in a JAR (as in glass) or a CAN?
Marbles in a can is the fateful sound of engine knock and/or the car running too lean on turbo charged cars...I don't know if this is the case for the M5 but the description of the sound is a good indicator.

Do you hear it more when you are driving close to a low wall or an island with brush that reflects sound? I hear it myself from time to time, and mine sounds like what the other fellow poster had said - Vanos.

What gas do you use? You might want to try switching gas and I assume you are using 91 octane at least right?
 

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does the noise happen with the clutch in or out? What you're describing sounds like normal gearbox "rollover" noise, if it's happening with the clutch out. Try pushing down on the clutch and see if the noise goes away. Normal for your milage.
 

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I highly doubt it is ignition knock. This car has very efficiant knock sensors and will pull timing way before you can or will hear audible knock as long as premium fuel is used. i am also sure he would be gtting ses or codes if he had audible ignition knock

Op do you have any loss of performance?


Ryan
Agree. You will not hear knock...Even if the knock sensors die, they will fail safe and retard timing.

OP- is it marbles WHIRLING around a jar? I think bearings- wheel perhaps? Is it related to road speed or engine speed? (ie 4--50mph no matter what gear under no or light load....versus 2800 rpm in any gear...)
 

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Discussion Starter · #11 ·
Does the sound resemble marbles in a JAR (as in glass) or a CAN?
Marbles in a can is the fateful sound of engine knock and/or the car running too lean on turbo charged cars...I don't know if this is the case for the M5 but the description of the sound is a good indicator.

Do you hear it more when you are driving close to a low wall or an island with brush that reflects sound? I hear it myself from time to time, and mine sounds like what the other fellow poster had said - Vanos.

What gas do you use? You might want to try switching gas and I assume you are using 91 octane at least right?
Sounds like marble's in a jar... The sound is pretty constant all the time.

I use 92 Octane as this is all that is available where I live. I know the car has a Dinan Tune and was formerly an Arizona/Cali car :confused:
 

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Discussion Starter · #12 ·
does the noise happen with the clutch in or out? What you're describing sounds like normal gearbox "rollover" noise, if it's happening with the clutch out. Try pushing down on the clutch and see if the noise goes away. Normal for your milage.
I hear it all the time whether it be shifting or cruising... I don't hear it when I'm WOT which might be normal because I'm usually not listening for it :M5launch:
 

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Discussion Starter · #13 ·
Agree. You will not hear knock...Even if the knock sensors die, they will fail safe and retard timing.

OP- is it marbles WHIRLING around a jar? I think bearings- wheel perhaps? Is it related to road speed or engine speed? (ie 4--50mph no matter what gear under no or light load....versus 2800 rpm in any gear...)
I seem to hear it most of the time. However, something you brought up has my attention. I sort of hear a "whistling" or "howling" sound whenever I'm cruising and lightly on the throttle. If I let off the gas, it goes away immediately ("it" meaning the howling sound). However, I still hear the marble sounds...
 

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Discussion Starter · #14 · (Edited)
Update:

So last night I picked up the car from the shop. It appears to be running great again though I still hear the sound. The torque seems to be down but I have been driving an 03 Z06 around for the last couple of weeks so maybe that is distorting my perception. My mechanic said he didn't hear anything out of the ordinary for the S62 engine. He said they're typically a noisey engine :dunno

Here is what I had done:

- all 02 Sensors
- All CPS Sensors
- Fuel Filter
- Spark Plugs
- Spark plug boots
- Valve cover gaskets
- Flush of the tranny and diff fluid with Royal Purple (shifting feels so much better btw)

In Feb I had the tstat replaced as well.

So for now, I will live with it but I'm going to go for a drive here in a bit and see if I can get a video clip of the sound.
 

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does the sound you hear seem like it's coming from the engine? Bearings or wrist pins would be my first thought given the miles, but you'd have to listen to the motor with a stethoscope to get a better idea.
 
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