I left the Max sitting for a week or so w/o running, when I started up today it made a rattling sound which went away within the second, sounded to me like a rod bearing which quiet down after it got oil
is this thing about to throw a rod on me? I got 130k miles, religiously change oil using synth, and I havent seen any metal shavings in the oil or any of that, car runs great actually

 

It's probably not a rod bearing. At most it's probably something in the valvetrain that just had all the oil drain off of it and made that sound until it got oil pressure.

If it starts happening after shorter intervals of downtime, you might want to look into it. Otherwise, don't worry about it.

 

im pretty sure the timing chain was rattling due to low oil pressure since the car had been sitting.

 

I agree with sooner...wow that was weird to type.

 

yea I thought valve train first, but it sounded like a deeper rattle than am use to hearing a valve train whcih is more like a ticking noise.....

never heard a timing chain rattle before so have no idea waht it sounds like....

 

should i be looking into replacing timing chain (and gears?)???

 

No, you should be fine. Just keep an eye on it and if it gets worse, then worry about it.

 

In my experience with rod's knocking,,, usually once they start they dont stop,,and progressively get worse,,usually quickly. one easy, quick test is to load the engine while in gear, (power brake) , just a little,, the knocking should increase in intensity if a rod,, but then again,what do I know

 

you should be fine. if anything, you might have to replace the tensioner (there is a TSB)

 

ok, thanks...I was sh1tin a brick for a minute there!!

 

If it was a plain bearing (main crank, big end/small end rod) it would definitely be more of a knock than a rattle and would get worse under load and with the engine warmed up. Nissan considers timing chain rattle for a second or so, normal after a cold start. On a cold start it takes slightly longer for the oil pressure to build than after a hot start. There are three chain tensioners that require oil pressure to do their job, and one lube oil jet which might not spray oil very well right after a cold start because of the cold oil's viscosity. This may be the cause of the noise (rattle) that you are hearing. Some people have (in theory) eliminated this simply by changing oil filters (a less leaky anti-drainback valve can help) and an oil change. Don't panic! Like someone above mentioned, if it was a bearing, it would be a consistant/persistant noise that wouldn't get any better.