P1CR

My 99 (27k) had a two minute valve tick yesterday. I started it (warm) and it was ticking. Drove a few miles and it went away.

Thoughts?

Only other thing I can mention is a slight rattle after cold starts that goes away in a minute or two. No idea what it is.

Waz996

Rattle: happened to me only on cold starts. It happened to be that the muffler has pipe bypasses inside it. One of those pipes had a weak weld so i had to open the guts out and reweld it, in the abscence of OEM and dealership here. But it's working just fine now, cost: $10!

Valve tick: I really wonder why some cars' valves tick on cold startup and then stop after a few blips..

Waz

TWA

I get the same thing in my '99. Has 34K on the clock. Seems to disappear once the oil gets to the top of the engine (valve train). That's what I can visualize as the cause anyway... I say that because it seems to happen after the car's been sitting for a few days between starts.

Kerry

Yep, in other cars you get that sound when the hydraulic valve lifters have lost their oil and it takes them a minute or two to pump back up. But on a Porsche...?

TWA

i'm not intimate with the design, but i'd think gravity effects p-cars too.

Kerry

Probably <img border="0" title="" alt="[Wink]" src="wink.gif" /> although if a German engineer could think of a complex way to negate it's effects... But do they use a hydraulic lifter on an overhead cam design? Or do the rockers ride directly on the cams?

NMoore

There are additives that moderate the effect somewhat, but it is as described some air in one or two of the hydraulic lifters. Perhaps that warm start was still with cold oil?