Well since warming up the car on these cold starts I haven't had any problems with it at all. Plus as someone had mentioned before, of moving the car in and out of the garage for a carwash, the car was on for literally 5 seconds and turned off that may have caused it. I've since been good with it and no sounds whatsoever. Had at least 1 oil change as well since then.

 

The information you are getting from your dealer is basically correct. Remember, your engine relies on several oil pressure-fed components(valve lifters, timing chain tensioners, etc.). Any or all of these can make some noise on startup until oil pressure is up and temperature increases.

Another note: The scenario of repeated cold starts(in and out of garage, etc.) over time can cause you another issue. On cold start, the ECM is dumping quite a bit of fuel into the engine to get it fired from a cold state. If the engine is shut off almost immediately after the cold start, there may be some unburnt fuel collecting in the backside of the intake valves. Over time this can lead to excessive carbon deposit buildup in the combustion chambers and intake valves. When these deposits get to an advanced stage, we have seen hard starting, rough idle, decreased fuel economy and poor overall engine performance as symptoms. Carbon buildup is a normal byproduct of the operation of your engine, but not letting the engine run for a few minutes when cold-started can cause you to require an induction flush/cleaning sooner than necessary.

 

So how long do you think is required on a cold start before engine shut off? When the RPM's reach below 1000 on idle?

 

pratik,

I get somewhat of a grinding/clanking sound immediately after the car turns over. Kinda sounds like those old diesel cars where you can hear the pistons moving up and down in the cylinders. but it goes away after about 1 second or so. it ONLY has happend on cold starts. It is a pretty bad sounding sound....almost as bad as when you 'restart' a car thats already on...i figure their is a second delay from the time the starter turns the car over to when the oil pump physically gets oil into the engine which is the cause of this noise??

 

Well I've only had this happen one time and this is an old issue (November last year) and this happened because I took the car out to wash and then brought it back in sot he car was literally on for 20 seconds or so and then turned back on and put back in and it did it again. I think that was an issue for me. I'm not so sure about yours. I just warm up the car everytime I get in though now.

 

this?
http://www.timware.org/g/g_noise2.wmv

I've been told by 3 dealers, including Grubbs, that its normal.

 

Tim,

Exactly that, except when the car first turns over...like right after u hear the whine of a car start and then the vroooom.....its that second in between the two...so whine of start...then the clanking...then vroom and a second later it dies into what you have on that vid file....i think its normal...but who knows...i think the 24'' spoiler on the hood and trunk, as well as the pink NISMO graphics i just installed should make the sound go away...

 

thats timing chain tensioner. Having had VQ30 Maximas before the G, I've gotten rather used to that startup rattle. Aside from verifying oil level, using the proper viscosity for your climate and using a proper oil filter with anti-drainback, not much to do. Shouldnt affect anything.

 

RATTLE, thats the word i was looking for....exactly. clank/clunk/tap/bang/grind...jeez...sometimes trying to describe a sound is harder than you think!

 

^ roger! it's hella hard if you're the only person there!

 

i got it too... and i cant check the oil cause the damn dip stick is angled like a damn puzzle. everytime i pull it out, the whole thing is covered.

 

Is the noise at startup a significant wear issue? i.e. if the rattle/clattering happens once, will this cause excessive wear on the valvetrain?