Split second rattle

[HDJ]

basically I started my car today, after it sitting cold for about 8 hours and upon startup for a split second a rattling sort of noise occurred. Now my car does have an exhaust rattle when cold on idle it only has a slight rattle not as loud as the split second one that occurred. I tried Revving and turning it on and off but i can’t seem to make the sound again. Also my car rattles in first when cold for 3 secs. Could it be timing chains?

 

[losh1971]

I'd say it's timing chains. Even though my engine is a Buick it, replacing the chain eliminated a cold start rattle and hot running rattle. Mine started out with a 3-4 second rattle upon starting, then eventually got bad when hot.

 

[HDJ]

It’s going for a service on Friday so should be confirmed by then. Just a quick update it did it again after letting it sit cold again for 3 hours. It happens a second after it’s started and lasts for two blinks of an eye on idle only.

 

[greenacc]

Sounds normal for Alloytecs. The question gets asked every week so it's very common. My car has made a very short rattle when started in the morning for the last 10 years and hasn't been a problem yet. Just make sure you change the oil regularly before it goes black.

 

[HDJ]

My cars a sidi LFX 2012

 

[lmoengnr]

Probably just the hydraulic chain tensioners bleeding down.

 

[HDJ]

Well she’s never done this rattle before only started today.

 

[HDJ]

This is exactly what it sounds like.

 

[greenacc]

Still normal. The oil pressure takes a few seconds to build up enough after starting to tension the chains fully.
Actually there's a nasty crunchy sound just at the end. That's weird because on mine the slight chain noise happens instantly as it starts. Yours was quiet then got crunchy.

 

[HDJ]

Well hopefully your right and nothing is actually wrong with the car as this only started happening today. Fingers crossed it’s not chains.

Still normal. The oil pressure takes a few seconds to build up enough after starting to tension the chains fully.
Actually there's a nasty crunchy sound just at the end. That's weird because on mine the slight chain noise happens instantly as it starts. Yours was quiet then got crunchy.