jmayzurk

Thanks to everyone who has already provided advice about getting my 993tt into shape. Now onto the next issue:

Upon starting the car, there is an intermittent "rattling noise" that goes away within a couple of seconds. It sounds to me like a bad bearing or pulley. I don't *think* it's lifter noise because:

(a) It doesn't always happen on cold starts. Yesterday I started the car after a week in the garage, and it didn't make any noise. But on subsequent warm restarts, the noise was there.

(b) The noise is higher pitched and more "rapid" than what I have heard when I've had bad hydraulic lifters on other cars.

But this is my first air cooled Porsche, so all of these noises are somewhat new to me.

I haven't had a chance to track the noise down (need to get a helper to start the car while I listen in the back), but I'm hoping this sound clip will allow someone to identify the problem:

startup sound clip (800k MP3)

I have RSR mufflers, BTW.

Any ideas? Thanks in advance.

-Jeff

911/Q45

I don't hear anything unusual Jeff. The cooling fan rattles on all of them, could that be it?

Peter S 993tt

Sounds fine to me.

sonny1

Looks good.,cheers,Sonny.

ttAmerica RoadsterAWD

Hmmm. Do I hear the sound of thrashing sand just after it fires up, then disappears? Is this what you are referring to? Sounds like someone's taking a long thin wired brush and slapping the cymbals on a drum set. I hear it, but don't know what it is.

Jaime

jmayzurk

Yes, Jaime, that's it. It never lasts for more than 1-1.5 seconds after the engine fires. If you listen carefully you can hear it in each of the three starts in the sound clip. Your description is a good one--it sounds like the fan just ingested a bunch of little pebbles and they're bouncing around against the fan shroud.

Who knows...based on the fact that several people said "sounds fine to me" it's possible that this sound is normal with these cars (re: 911/Q45's comment about the fan rattle) but I just don't have enough first hand experience with 911s to know.

Thanks,

-Jeff

ttAmerica RoadsterAWD

Hmmm. I don't have that sound in my engine. Maybe you can unplug the coil and have someone turn the engine while you check. Or, replug the coil, get a 4foot hose, one end in your ear, the other as a stethescope while a friend turns it on and you can fixate your ear onto the suspected area.

Jaime

ttAmerica RoadsterAWD

Ok, new thought. Do you know if your clutch housing vent is connected to the airbox? I'm thinking possibly, just possibly you have too much clutch disc garbage tubling/rattling in there? There is suppose to be a hose which effectively sucks out debris somehow. Others can chime in on this if it's a feasable explanation.

Jaime