Bob in NY

When my 07 TT is idling it has a "rattling" sound. It almost sounds like a throwout bearing is going but that's not it. I'm bringing it to the dealer next week to see what they think. Has anyone else experienced this sound? In 21k miles this is my first potential issue.

Thanks

avader906

Anything from exhaust leak, bad cats to bad waterpump and/or one of the pulleys. Need to listen to the noise.

Bob in NY

Yikes! Makes sense, I'll let you know after I bring it into the dealer.

Macster

I take it the car is a manual? The noise then might be some clutch disc or gear/input shaft rattle that is normal noise. A way to 'test' this is to when you hear the noise fully depress then release the clutch pedal. The noise -- my experience with my Turbo and other cars which also have exhibited this noise -- is the noise stops until for instance the next time I bring the car to a stop with the transmission in neutral and the clutch pedal released.

A more involved way to see if the noise is coming from the water pump or another accessory drive is to remove the serpentine belt and start the engine and let it run for a while. This only works if the noise is present from a cold start. I'd not recommend a hot engine, warmed up engine, be done this way.

Anyhow, that's a bit much for the average owner to attempt.

Best to do like you've decided. There's nothing wrong with taking the car in for a check up. That's what the new car warranty is for. Rare but something else might be going out. 21K miles is not that many miles. The car of course comes with a 50K mile warranty and the car is not even half way there yet.

If something else causing the noise, you'll catch it early and get it taken care of.

Sincerely,

Macster.

Bob in NY

I listened with the clutch depressed and the sound didn't change. My mechanic noticed it and suggested I take it to the dealer since it's under warranty. My appt is for next week so I'll see what they say. Thanks

TT Surgeon

On a NA car I'd suggest a intermediate shaft issue. Sometimes if the timing chain has some slop it will rattle.

E55AMG

Good luck Bob. Let us know what they say.

Bob in NY

Do you think this is something the dealer would repair or just let it go?

Bob in NY

Will do Chris

TT Surgeon

prolly repair

avader906

dealer should be able to diagnose. getting the belt off on 997tt - you need to remove airbox + undo y-pipe and hoses. to put it back you have to remove the bumper + the muffler, better done by the dealer on a car with a warranty. timing chain would have other implications with a CEL. it should be a trivial issue - i am seeing more and more 20-30k mile turbos with waterpumps + tensioner pulley, it has a characteristic sound. i would recommend searching youtube for 996 or 997 waterpump noise.

ps: i would advise against running the engine with serpentine belt off. just turn waterpump, alternator and all the pulleys by hand once belt off - if any bearings gone you will feel it by touch and also by sound.

Macster

If the noise is out of the ordinary the cause should be addressed regardless.

Be prepared. If you hear 'they all do that' to ask that this be demonstrated to you using another comparable car.

If you get any pushback point out that one major factor in your purchase decision in buying this car and from this dealer -- if you bought the car from this dealer of course -- was this dealer stressing its factory trained highly experienced service techs working in a state of the art repair facility and there's no excuse for the dealer not being able to well deal with this noise appropriately. Suggest that if the dealer continues to balk that perhaps the dealer misled you concerning its servicing capabilities and wonder out loud if you might be a victim of consumer fraud.

Don't go overboard and don't do the above until you have exhausted other means to get the dealer to stand behind the product.

The 997 Turbo with the old (996 Turbo) engine has a intermediate shaft -- though quite different from the IMS in the NA engines -- that I read can occasionally (read rarely) account for some rattle. But these occurances are as I said based on what I've encountered here and other places and in talking to techs I come in contact with are rare.

A chain tensioner can develop a leak or in some other way develop a problem that prevents it from maintaining proper tension on the chain and this can account for untoward noises.

A zero-lash lifter can get noisy or even a fuel injector.

The noise might even be from outside the engine -- from a noisy accessory drive -- or an exhaust leak.

You are entitled to have this noise characterized as to whether it is normal or not normal and if not normal to then have the source id'd and addressed.

Sincerely,

Macster.

Bob in NY

Thanks for the advice Macster, I didn't buy the car from the dealer who will be servicing it but I'll see if being the biggest Porsche dealer in the US means they have great service too.

Bob

E55AMG

Let's start taking bets on whether Bob hears the infamous - "they all do this" or "this is normal"

jhbrennan

Most likely but I really do like Macster's suggestion to have the service manager immediately go out on the lot and fire up a comparable car and listen to it.