jar of marbles sound like in engine

[PMPB]

This sound is most likely due to the pumping effect of the drive train turning the motor. There is no combustion, but a lot of air is still being 'dragged' through the engine as a result of deceleration. You'll notice that the sound changes immediately around 800rpm as the motor starts feeding some gas back in to prevent a stall.

[tintumz22]

Originally Posted by lickitysplit

Are you hearing it at idle shortly after starting the engine. Thats also clutch chatter

Nope. Not present during idle.

Originally Posted by Grip Ronin

bad timing chain tensioner? they normally are looser off throttle. im not sure if these run on oil pressue like s2k

when i search for engine jar of marbles like sound that words pops out.

Originally Posted by PMPB

This sound is most likely due to the pumping effect of the drive train turning the motor. There is no combustion, but a lot of air is still being 'dragged' through the engine as a result of deceleration. You'll notice that the sound changes immediately around 800rpm as the motor starts feeding some gas back in to prevent a stall.

hmm. i'm getting your point. i'm just searching through and want know what is going on. Thanks.

[Grip Ronin]

ya my girls maxima has a worn timing chain right now. its over 100k unchanged though, that is the maintenance interval so im sure your under that. you could very well have a faulty tensionor and the chain is slapping the front cover

[stugray]

holy wild guesses batman!

I'll try - Its the....passenger side seat belt retractor

[wheelhaus]

Originally Posted by PMPB

This sound is most likely due to the pumping effect of the drive train turning the motor. There is no combustion, but a lot of air is still being 'dragged' through the engine as a result of deceleration. You'll notice that the sound changes immediately around 800rpm as the motor starts feeding some gas back in to prevent a stall.

This gets my vote. You're probably hearing drivetrain chatter/lash, it sounds like the gears being pushed/pulled from slight accel/decel when the drivetrain transitions from engine load to engine drag, the drivetrain kind of bounces a little bit. If you barely tap on/off the gas it'll repeat, but it only happens when the clutch is engaged. Disengage the clutch, sound disappears because there's no engine load.

The reason you hear it below those rpm in 1st through 4th is because the engine noise masks it at higher rpm and higher speed/road noise. Also, at higher rpm, parts of the drivetrain are spinning faster, so on/off throttle transitions happens much quicker.

edit-btw this is completely normal. I think stiffer bushings help reduce it (and the rubber band feeling in the drivetrain) but nothing can completely eliminate it.

[strat61caster]

My car does it too, it's gotten louder over the last 6 months or maybe I'm better at picking up abnormal noises.

90% sure it's flywheel/clutch rattle, I posted this video in the thread linked above:
Edit: combined with gears and slop in the drivetrain mentioned by wheelhaus above, I wouldn't worry. Drivetrain failures (from the motor output to the wheels) so far have been a rarity, especially if you're stock.
[ame="https://www.youtube.com/watch?v=y7DE4iPLOhE"]Clutch Plate Faults - When a rattle is clutch plate springs and not a gearbox fault. - YouTube[/ame]


This pops up on Subaru forums all the time with the standard Exedy clutch replacement. Rode in a buddy's WRX who just got a new Exedy put in and it was louder than my FRS.

[tintumz22]

Thanks everyone! I'm understanding what every posts and how it's working and where it is coming from. I really wanted to take a course related to mechanic stuff. Just to have an idea of everything. But with people here i get to learn stuff already. Thanks thanks!


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[extrashaky]

Originally Posted by smbstyle

Yes, that's normal.

Has anyone noticed how often that phrase gets used around here?

I'm waiting for the thread where someone posts, "Today I was taking a hard turn on a back road at 7000 RPM when demonic fire enveloped my car and Satan materialized in my passenger seat offering me unlimited track access. Has anyone else had this problem?"

And then someone else responds, "Yes, that's normal" and includes links to other threads where the issue of drivers inadvertently summoning demons has already been discussed.

[smbstyle]

Originally Posted by extrashaky

Has anyone noticed how often that phrase gets used around here?

I'm waiting for the thread where someone posts, "Today I was taking a hard turn on a back road at 7000 RPM when demonic fire enveloped my car and Satan materialized in my passenger seat offering me unlimited track access. Has anyone else had this problem?"

And then someone else responds, "Yes, that's normal" and includes links to other threads where the issue of drivers inadvertently summoning demons has already been discussed.

Yeah, it gets used a lot. Wanna know why? Because the same questions get asked a lot, and a lot of users are analyzing every little noise they hear, which many are.... you guessed it! NORMAL.

OP asked if we hear that sound (didn't ask for the mechanical engineering explanation as to what caused it), and the appropriate answer is "Yes", and to make the OP sleep easy at night, I added "that's normal".

[wheelhaus]

^ I do the same thing, but always try to explain why or what's causing it. Just saying "it's normal" sometimes doesn't help, and sometimes is only to troll (I think that's what extrashaky is getting at). There's always a chance (more like a guarantee) that everyone will have a different explanation. Hopefully one nails the OP's problem accurately.

I only get worried if the OP's explanation is accurate for a completely different problem, but due to the OP's possible lack of knowledge or misinterpretation of the symptoms, is told "it's normal" when in fact, it's not and needs serious attention. We can only do so much for each other through internet typing and shitty cell phone videos... lol

[extrashaky]

Originally Posted by smbstyle

Yeah, it gets used a lot. Wanna know why? Because the same questions get asked a lot, and a lot of users are analyzing every little noise they hear, which many are.... you guessed it! NORMAL.

OP asked if we hear that sound (didn't ask for the mechanical engineering explanation as to what caused it), and the appropriate answer is "Yes", and to make the OP sleep easy at night, I added "that's normal".

Relax. I wasn't criticizing your response. I just find it entertaining that this car has so many odd quirks that are "normal."

Originally Posted by wheelhaus

^ I do the same thing, but always try to explain why or what's causing it. Just saying "it's normal" sometimes doesn't help, and sometimes is only to troll (I think that's what extrashaky is getting at).

Not at all. I thought the links did a good job of providing background on the problem. Again, I wasn't criticizing.

[wheelhaus]

Ah right, now I get what you're saying.