Hi all!

I have a quick question for you. I recently bought the G37x 2009 with tech package (what a car!!). However, I noticed that on cold start, the engine makes noise like an old car close to retirement!! The noise is like if the valves were not lubricated enough and would therefore make a metal noise for around 60 seconds (then, everything comes back to normal sound). I used to have a g35 2007 that would sometime make a similar noise but not to the extent that the 2009 one does.

I appreciate that the 2007 and 2009 has different engine. However, I would like to know if this is normal! Apart from cold start, the engine does not make any special noise.

Thanks for your help!!

Daniel

 

I've noticed the same thing with my 2009 sedan. It's loud and sounds like an old cranky engine until it warms up. Then, things are quite and smooth. Strange.

 

I noticed when cold starting, the engine would stay at 1.1-1.2 RPM to warm up the car faster. It drops back to 500-600 RPM when you put to D or the engine is done warming up.

 

Its the VVEL system. It appears harmless...i have it too. I think the Nissan Ester oil cures that...but at 12 bucks a qt.....i'll live with 30 seconds of noise.

I don't even think about it anymore.

 

Nothing similar noted on my 09. Started it this evening at 6F after sitting outside for 24 hours. Now minus 8 F and should be about minus 15 in the morning. I MIGHT go out and try it then just to see how it fares.

 

i dont feel a lone anymore

 

Okay so only minus 10F shown on the readout (officially minus 18 at the airport). Car started right up and went to 1400 rpm (as would be expected at those temps). Did not sound noisy in the least. Gradually went down to about 1000 rpm in the minute or so I was stupid enough to set there looking at it. 1500 miles on the car. I have no idea what oil is in the engine, what ever came from the dealer - not changed yet.

 

I think the noise in question is not the VVEL helicopter noise but a typical cold start related rumble. I've noticed it as well with both the windows open and closed inside my unheated garage and sounds like cold valve lifter rumble and barely lasts 30 seconds. It's not a lubrication issue since oil pressure builds within seconds. This is consistent with other cars I've had especially my prior Corvette whose LS-1 engine was much noisier under similar conditions for a short time after cold startup. Personally I consider this normal for a performance engine.

 

If this noise is normal why do some examples not have this noise under similar conditions?-sounds like mfg tolerance stack makes the difference if your engine is noisy or quiet. With that being said decreasing the acceptable mfg tolerance range would assure a greater percentage of engines would not exhibit this irritating noise.

 

Okay so only minus 10F shown on the readout (officially minus 18 at the airport). Car started right up and went to 1400 rpm (as would be expected at those temps). Did not sound noisy in the least. Gradually went down to about 1000 rpm in the minute or so I was stupid enough to set there looking at it. 1500 miles on the car. I have no idea what oil is in the engine, what ever came from the dealer - not changed yet.


Ok..not that cold here: it's a balmy 7F. Absolutely no chattering with hood closed or inside car. Pop the hood and stick head inside and I hear it, but not loud. I use Redline which is an Ester Oil.

 

Built and raced motorcycle engines for years in my youth
and have owned 23 New cars at last count. (that's my
credibility and experience...I'm old ok?) POINT IS I can't
believe how some, including mechanics discount facts.
Metal-to-metal noise is just that! It is never normal
or "OK"...it is sure evidence that metal-to-metal contact
is taking place without proper lubrication...period.
Considering the well known fact that MOST ENGINE
WEAR OCCURS ON STARTUP, and that we're talking
about a "state of the art" engine in a $40K car is
more amazing......Have it looked at. There is
plenty of evidence and documented cases of
premature VVEL actuator and motor damage
occuring from poor lubrication. Truth is
it's not alway just a sympton to be fixed
by a "re-flash" and an oil change. Personally,
I would insure a dealer accomplishes the TSBs
and documents that there is no damage within
the VVEL system to include the actuator and
motor mechanisms. You've got nothing to
loose by taking these measures.... Here is
some more information. Good Luck

Revenge of the Nerd - Nissan in the sump with diamonds?

 

I read your article and all other posts. It's interesting info but seems to be based on extreme conditions and also seems to leave some details out about the findings. Many people on here have experience and I won't start a resume contest, but a cold start rumble does not imply metal-metal wear/damage by itself. An engine that goes from <15F to 220F will experience variations - ALL engines sound different when starting below freezing compared to normal operating temp. That's why you should always drive slowly in cold conditions until the engine reaches operating temp.

We must each do what we feel is best, but 20 seconds of a cold engine rumble (not metal clanking or worse) is not the same as an engine that exhibits similar noise constantly especially at higher RPM where the stresses are much higher.

 

While I agree that most of us probably know the difference betweeen
3-5 seconds of extreme cold start "chatter" that is not what is described.
He says...." I noticed that on cold start, the engine makes noise like an
old car close to retirement!! The noise is like if the valves were not
lubricated enough and would therefore make a metal noise for around
60 seconds..."

Considering his description and that any 5W oil will flow well below
zero......he's got a problem. He clearly describes "metal
to metal" noise for up to one full minute. That is not normal.

You don't agree that insuring the TSBs are done and having
a dealer check it out is a good idea on a G37x that can't be over
one year old that should be under warranty?

 

I'm basing this purely on memory, so take it with a grain of salt, but.....

I thought I remembered reading about this. Something to do with secondary air injection, emissions, and the fact that this noise is completely normal at start up. Like I said, this is purely based on memory, but I'm pretty sure I read this either here, or an a different G forum.

Some people need to quit with all the hysteria. If this is anything like the sound I normally hear at start-up, it's NOT metal on metal.

 

BS- metallic clacking on start-up is not normal- if you argue it is, are the G;s that don't clatter the ones that have the problem??? hopefully you see my point LOL These engines do not have an active air injection system. If you as an individual choose to be in denial, that is certainly within your dominion-carry on.