'03 with 60k,, very noisy start up this am,, temp was 65. never heard this before,, sounded like throwing steel ***** into a metal drum,, for 2 seconds,, turned off the engine and restated and got the same thing for another second and ran normal there after

anyone experience this?

 

Steel ***** into a metal drum?!? Very small ones? That sounds like detonation to me. If it's very hot out and I am above 8psi on my SC near redline it sounds like that. Very bad!

 

Happens sometimes when all the oil drains back down into the crankcase after a hot spirited run.
Until the oil pump does its job and raises oil pressure again, all the bearings and moving parts have no oil.
As long as it doesn't happen often you should be fine.

Another source of that clattering sound is from the timing chain tensioner at the front of the engine which can also become dry of oil. Until it gets lubed, it can make a nasty noise too.

BTW, make sure your oil is clean and up to level too for obvious reasons.

Welcome to 'Driver, btw......

Colin.

 

Good advice!

 

its beyond the oil drain down theory,, this engine has always been very quite when starting,,, i dont understand all of the setup regarding variable timing but i'm thinking its related to that,,, this was very very loud rattling

 

Sounds like it might be the timing chain. Common on other nissan vehicles.

 

Yes, this does happen alot to the earlier VQ35s (circa 02-04ish). Supposedly this problem was corrected from somewhere midyear 03 to somewhere 04...

My Altima (3.5) does it just about everyday, just not to the extent you describe. Usually only on the first start of the day. More of a fast rapping for about one second.

The Infiniti does this, perhaps once every five starts. It seems much better than the Altima.