two engine noises
 

two noises i'm wondering about coming from a 2002 that i just bought used:

1. on cold starts, i'm sometimes hearing a brief high-pitched whirring noise about a second after the engine starts. lasts for about a second or two. sounds like the starter or a belt could make that noise, but the owner claimed the starter was replaced within the past year or so.

2. after turning off the car, the back exhaust/muffler system is loudly tinkling for several minutes before it cools. sounds as if little metal bugs are hopping around in there, but it's probably just the sound of the hot metal cooling. still, does that suggest a problem?

Number 2 is normal...enjoy the symphony

Number 1 is not...best present it to someone who can hear it person right away...someone who knows these cars

#1 could be the starter gear hanging up and not retracting right away? I fixed that problem on my wife's RSX by pulling it and cleaning/lubing the bendix assembly.

On #1, you mention a high pitch whine, but only for a few seconds. There is an air pump that turns on for about 75seconds at start up. The noise is much more prominent on my 98 Box than it is non my 00S.

#2 sounds like the exhaust and cats cooling off. Not a problem.

For my two cents worth there are three possibilities for option 1 that I've been looking in to:

1) Secondary Air pump that kicks in for 30 seconds but only on full cold starts.

2) Bendix (hope I spelt that right) spring on starter.

3) Cam chain slap.

Number 3 is what has me concerned. It can occur on a cold or hot engine. I do occasionally get it, but people say that it too is somewhat normal and can be reduced by using different oils or replacing the cam chain guides.

FWIW, my starter does sometimes have the squeal and I do occasionally her the cam chains. I don't worry about the squeal and when I crawl underneath it I'm going to see about removing the starter and spaying or greasing the starter shaft to see if that alleviates the squeal. But the cam chain noise worries me. It is just occasional, but it worries me. If/when I have the clutch replaced, I'll get the IMS replaced, and at the same time will replace all of the cam chain guides and possibly tensioners too.

My '03 does both also and noise #1 only happen on a cold start and for 1 second, it sounds like when the syncho on a manual tranny is bad and you try to shift it into gear (gear grinding noise). It's probably something to do with starter and I've tiptronic. Should we be concern?

I too have #1 issue and have not heard a definite answer on whether it is the starter of the chains.
Boxster startup noise - YouTube

After listening to your video it sounds like the cam chain slap. My starter noise is much higher pitched and sounds more like a whir sound than that. My cam chain slap sounds similar to your but seems to last at least twice as long. When it happens. I just had my oil changed at the local Porsche dealer and am waiting to see if I hear the noise again. I expect I will sometime as I doubt just changing the oil will entirely remove the noise based on prior threads.

yeah, by #1 noise is also more of a high-pitched whirr rather than anything that sounds like grinding.

actually, it hasn't really happened the past few starts and seems to be more of an issue of cold starts after several days of inactivity.

This is exactly what I hear on a cold start.

Not to hijack, but can anybody help with my noise...

I have a '97 with 62,xxx miles on it. On cold start-ups I hear a "rattle" when the car first turns over. It sounds like maybe an exhaust sound or something else that is shaking a bit. Again, this is only at cold start-up. Other than that, I never hear the sound and the engine/exhaust sounds pretty sweet when driving.

Any ideas?

Thanks

Actually, I just listened to the YouTube video and my sound is quite similar; just not as "harsh" sounding.

Could it be the same thing? Is this an issue or am I ok?

Signed,
A newbie who has bad IMS dreams