Does your Boxster rattle on startup ?
 

and how long does it do this ?

What rattles?

The timing chains can rattle before the tensioners pump up.
Mine does, for about a second after the engine fires.....

Listening out this morning after seeing another thread on the topic, I had a small rattle for a second or two then gone.

Not 100% of cold start ups
Mostly after it sits for many days

Neither my cars original engine 2.7 2003 (42K) or the rebuilt 3.6 (21K) make any noise when starting.

Mine has just recently started doing this, but only for a second after cold startup, and usually only after sitting several days.

I did used to have some rattle but I think it was from the exhaust, like a heat shield or something, now that I replaced the 2nd cats with test pipes it has gone away.

Steve

mine rattles for a second or so after startup, more if it sits for several days, the rattling stops at the same moment the oil pressure light goes out. There is an o-ring between the oil pickup tube and the pump suction and I plan to replace that to see if things improve. I am thinking to replace the spring and plunger in the oil pump relief valve to see if that improves things, 2nd step is going to be an oil pump replacement. I will post the results of these efforts as I plan to do them one by one

Sounds like lifters or cam chain to me, but my mechanic says that rattle--only when really cold and not run for a few days--can be IMS bearing.

chain rattle , my 03 s does it after it has been sitting for awhile . my 996 3.4 does it more often.

Mine rattles on start up and gets better as it warms up...also rattles at lower rpms when accelerating between 1000-2400 range. Was told it might be one of my cats because the sound seems to be coming from the exhaust. Getting a full diagnosis later this week.

Mine doesn't rattle when its cold or when its hot... It used to rattle for about 3-4 seconds on cold starts before I changed the cam chain guides, tensioners and variocam pads; But I haven't heard it since the rebuild :)

No rattles here, even if the car sits for a week which it usually does. I'd be worried about any rattles.

Steve

No rattles during start up. But, I think I hear one when I am at really low speed and low gear.

Mine has the less than one second rattle on startup when cold and hot if its been sitting for a couple of hours.

Sounds like your rattle is from lugging the engine. Do you hear it when you accelerate or at an even throttle. If its under acceleration then you're lugging the motor, not good.

When I first got my 986 it rattled for a second at startup. But during the IMS bearing install I pumped up the two removed chain tensioners in a pot of fresh oil before replacing them. After that no rattle at startup. It may be the two tensioners were "gummed up" somewhat since the car had barely been driven in the two years before I bought the car this past February. The dealer changed the oil before my purchase so this was also the second oil change in maybe 2K miles.

I suppose I could do the same for the Bank 2 chain tensioner too. But it faces downward so it's likely to drain between uses...so maybe it's less likely to get gummed up from used oil siting in it.

found my problem. It is a loose heat shield on my rear right cat.

is this about the sound you hear with the startup?
only does it on the very first cold start, can turn the car off and on and it wont do it.

Is this the lifters?

https://youtu.be/OhXTLetpVVc

Mine's rattles at startup for a second 1st start of the day or after car sits for several hours. Read somewhere that the flat six tends to do this after so many miles. My car has 137k with IMS done