Ericson38

Initial startup sounds like our 997.1 MT C4, but the rattle that starts a few seconds latter and then goes away before he backs up does not sound normal to me. Not sure why it would take a few seconds to develop the other sound, which then goes away.

LexVan

Np519, send Flat Six a PM. Have him listen and render opinion. Is this bore scoring??

braymond52

Same here - I get a little rattle for a few seconds after I cold start the car. Doesn't happen when car is warm. I've had other cars that are a little noisy when cold starting so I think it's fairly normal.

teebone

I get the same. 2006 c4. Just a few seconds of rattling when cold start. Goes away. Never worried about it. Maybe I should?! Will have mechanic check it next time I'm in. Soon car will be tucked away for winter anyway. Always a bummer. Time to move south!

gpjli2

Rattle on cold start is usually timing chain and/or tensioners. I'm not so sure that is what op is hearing. More of a knock than a rattle imo. Wouldn't be too quick to call it normal w/o having it checked out. Better safe....

BIG smoke

1o,ooo kms and 1 year since last oil change?
First thing, for me, would be to change the engine oil.

In my truck ---Fresh oil, engine, diff, transfer case. Thing quietens right up.

New engine oil will at least take that out of the option list.

kozzimo55

Sorry to bring this back up, but I have the same noise. Did you have it diagnosed?

Chipster

The noise you are hearing is just your chain tensioners re-pressurizing. Completely normal.

gpjli2

Responded to this in 2015. Timing chain is more like a rattle. As I do hear a 'knock' now I am not sure. If it is a bottom end noise it could be $$. I'd take it in to shop if I were owner.

kozzimo55

The previous owner had been running Castrol 5W-40. What is really interesting is that a few days after I switched back to Mobil 1 0W-40 the noise has greatly decreased.

Since it is an easy job to perform, I think I will swap out the tensions soon when I find some time. I will report back with the results.

byrona8

Reviving old thread.

I just got the same noise.
What did the OP do to resolve this?

Thanks

Racetwin2

If it disappears after a few seconds it's just oil filling up engine. Hydraulic Lifters are known to have this ticking noise sometimes. As previous poster said changing oil can help. It's cheap and easy as first check.

If ticking noise stays I would leave it for professional check up.

groovzilla

Sounds a bit like the PSE(Porsche Sound Exhaust) gurgle sound - throaty gurgly noise - Does your car have PSE??