[NBman]

I posted this on the other forum, but I think it belongs here.

Anyway, I've been hearing rattling noises under my car for a couple of months now, but it's not consistent. The sound is coming from the front either by the wheels or mid section, but certainly not from behind. I usually hear this rattling/grinding sound when I accelerate from a complete stop. For example: I drive for 30-40mph, stop at a red light, wait a few minutes at the light, then when I accelerate I hear the noise. After accelerating for few a seconds, the rattling sound goes away and everything sounds normal. There is no grinding sound if I stop and don't idle for a few minutes.

I recorded the "rattling/grinding" sound. If you have time, please listen to it and let know if it sounds familiar.

Basically, in a empty lot, I drove 20-35mph, stopped for 2 min (to simulate stopping at a red light), then accelerate again.

In the MP3 file, you should hear the "rattling/grinding" at the beginning of each acceleration, but it goes away soon after. The sound is distinct and you should be able to distinguish it from the normal engine/exhaust. I edited the sound to include four samples.

Sound Sample (25sec):
http://www.renderphase.com/site/temp/nbsoundgrind.mp3
Right-Click and save-as

Any ideas would be appreciated.

Car: 1999 NB 2.0L GLS ~35K

 

[73standard]

It could be tie-rod ends going. I a problem like that with my '74. It woudl occour around a certain speed, then just go away.

 

[Pulgamovil]

My down pipe gasket sounded pretty much the same it had a very small leak and the sounds is similar, wait a week or so if it gets worse....the gasket has a leak and has to be replaced

 

[speedie]

When a cat coverter is going bad it also sounds like rocks rattling in a can.

 

[73standard]

It doesn't feel like it's jumping does it? As in running over a lot of rocks?

 

[Porkchop]

Okay, since I can't listen to MP3's here at work and since we're all just swinging at the pitches anyway:

How about wheel bearings?

 

[Fowvay]

I tried to listen to the file but it said it was unavailable.

I know that a number of people have had welds break on the cat heat shield which will cause a rattle when it gets heat soaked and the pipes stretch enough to allow contack with a metal surface. I would crawl under it and check to see if there is anything loose... um ya make sure its on jack stands and you let it cool over night.

Tom aka Fowvay

 

[AmyJane]

My car made the same noise when the heat shield cracked.

 

[NBman]

Speedie: It does not feel jumpy/riding-over-rocks when I hear the sound. The ride is normal, when I hear the grinding/rattling.

Pulgamovil: This sound has been going on for months now and it's not getting worst. It's pretty much the same as when I first heard it. The sound doesn't come on all the time, so I didn't bother with it.

The rattling only appears during acceleration after I idle for a couple of minutes at a stop light. Basically, when I drive 30-40mph, stop at a light for a couple of minutes, then when I accelerate that's when the rattling sound comes up (and disappears after a few seconds). There is no rattling if I start the car and drive off, OR if I stop at a stop sign and instantly go.

Pulgamovil: When your down pipe gasket had a leak, was the rattling/grinding consistent? Or did the sound exist only during acieration from a complete stop?

CyberGreenBaby/Fowvay: When the heat shield cracks, will it make a rattling/grinding sound all the time? Or does it only appear during acceleration? BTW, I don't have the tools to get underneath and I can't fit down there. I'll try to visually inspect it from the sides. (Also, above posted sound file should still be up)

Porkchop: About the wheel bearings... I think I might have a problem with that too, but the sound is different than this rattling. Recently, when I turn the wheel slightly to the right while going straight, I hear this loud squealing sound like a small bird singing from hell. The sound is off/on again, so I can't reproduce it all the time.

 

[Pulgamovil]

Mine only did it when accelerating (in myy boost gauge above 3 psi), it was fairly consistent for like 3 months then it began making more noise little by little. When idling or coasting IT NEVER MADE ANY noise.
Eventually I changed my downpipe and cat along with the gasket and my bug now is as quiet as ever...

If you dont want to spend a ton $$$ trobleshooting this, wait till you have a cel or it makes more noise, then you will know you have a leak or the mesh in the c downpipe/cat has a fisure and it makes noise.

If you do you will get a CEl indication Catalitic converter below treshold efficiency.

 

[73standard]

It does not feel jumpy/riding-over-rocks when I hear the sound. The ride is normal, when I hear the grinding/rattling.

Ok, then it's more than likely not a tie-rod. Sounded like it at first though.

The rattling only appears during acceleration after I idle for a couple of minutes at a stop light. Basically, when I drive 30-40mph, stop at a light for a couple of minutes, then when I accelerate that's when the rattling sound comes up (and disappears after a few seconds). There is no rattling if I start the car and drive off, OR if I stop at a stop sign and instantly go.

How is your AC? It could be your compressor going. Mine just did that two months ago. I would be a stop light, and go, and around a certain speed (can't remember exactly) it would sound like a base ball card stuck in bike spokes (only louder and worse).

 

[AmyJane]

CyberGreenBaby/Fowvay: When the heat shield cracks, will it make a rattling/grinding sound all the time? Or does it only appear during acceleration? BTW, I don't have the tools to get underneath and I can't fit down there. I'll try to visually inspect it from the sides. (Also, above posted sound file should still be up)

Mine didnt make noise all the time. I could also hear it sometimes if I was parked and revved the engine a little bit. It was only when I accelerated from a complete stop or if I was going really slow and sped up. I'm assuming you're not covered under warranty? If you are they'll fix that under warranty..they did mine. Good luck!

 

[NBman]

I just wanted to update this for others who might have similar problems (and complete the thread).

I brought in the car to the dealer a couple of weeks ago and the problem was:
"The center exhaust support was rusted where it attaches to the center pipe."

They fabricated a new bracket for the center exhaust. They charged $50 for the whole thing. At first the service advisor thought it was the catalytic converter and was about to replace it under warranty, but after the tech tested the cat converter, it turned out to be ok.

Replacing the bracket did not completely fix the problem, but fortunately the rattling sound isn't that loud anymore and doesn't appear as often. I should have asked them to check the heat shields, but I thought they'd check that while doing the diagnoses.

Work was done at Ed Murphy VW in Schaumburg, IL.

 

[BUGSTUFF]

Our '98 had the same problem. Repaired on November 14th for $56 which included a new clamp and labor. Also by Ed Murphy VW in Schaumburg. Our rattle is completely gone - maybe that's what the extra $6 was for. ;-)

NBman, where are you located?

 

[NBman]

Our '98 had the same problem. Repaired on November 14th for $56 which included a new clamp and labor. Also by Ed Murphy VW in Schaumburg. Our rattle is completely gone - maybe that's what the extra $6 was for. ;-)

NBman, where are you located?

Hey Bugstuff, I think I bought some Fog Grills from you a long time ago. The Grills are still on the Fog Lamps

Anyway, you mentioned that your Bug had the same rattling sound on the center exhaust pipe that mine had. When Ed Murphy replaced the "clamp", did they list a part number on your invoice or did they simply fabricate a clamp?

Do you remember which Primary Tech (Number) worked on your car? The next time I'm there maybe I could request for the same tech to look at my car. Just private message me the info if you wish.

The price was actually $55.XX for me...

 

[BUGSTUFF]

Here's the description from the work order:

Check Exhaust Hangers/System
Found Mid Muffler Hanger Broken
Resecured Mid Muffler with Clamp
Part - Hose Clamp $1.95
Total Parts & Labor $55.45

Tech number was 392.

Also had the valve cover gasket replaced under warranty and the brake fluid flushed.

See ya!

 

[TeddyTiger]

Felt like I needed to refresh the topic, I get the same loud rattle around 2000 RPM while I'm decelerating. I know it's definatly coming from underneath the car, the stealership wanted like $70 just to put it in the air and diagnose. Ugh, I'm wondering if I should just take it to an exhaust shop.

It only happens after I've been driving for a while, so I know it's when something heats up.

 

[baddassbug]

mine rattles when im sitting still and step on the gas pedal sitting still to rev it up i hear it around 1000-1200 rpm on the way up and the way down but it only does it after it warms up a bit ill have to put it on the lift and check teh heat sheild on the cat wouldnt surprise me it has 102000 on it now

 

[NBman]

Just a quick update:

My MIL/Check Engine Light turned on recently and it was caused by the catalytic converter. They replaced it under warranty and now there is absolutely no more rattles!

http://www.newbeetle.org/forums/showthread.php?t=8976