And If anyone asks, the oil is filled to the proper level between the H dot and L dot (closer to the H Dot). It has Pennzoil 5w-30 full synthetic in it with a Pennzoil filter (I don't think this filter has an anti-drainback valve, correct me if I'm wrong?). Oil change was done almost 4 months ago, since then I've only driven 1,300 miles or so. This odd sound started happening a month ago and seems like timing chain tensioner noise? (Really hoping it's not). I fear it may get worse if I continue to ignore it. It is quite audible inside and outside the car. The SES light is not on at this time, although work was performed when there was incorrect green fuel injector installed (A fuel injector for a 350z actually..) causing a random/multiple misfire. I had this diagnosed and repaired at the Infiniti dealership. The SES light went off instantly and has not come back in a week, which now basically tells any technician, including Infiniti, that the engine is operating normally and nothing is wrong but something is wrong, you and I can hear it from the video. This only happens on cold starts. This is the 2009 coupe, black, and manual.

I'm going to start with changing the oil with Mobile 1, since I guess a lot of you use it with no issues and switching the oil filter with OEM. Is my baby dying?

 

Sounds like a bad catalytic converter. Does it rattle at low rpms?

 

it doesn’t, they are no cats, test pipes are in its place.

 

Timing chain or chain guides.

 

I don’t believe it is related to your timing. Sounds like a when an engine sits and all of the oil drains down to the oil pan. Initial start up sounds horrible because there is no lubrication throughout the upper and lower parts of the engine. But I could be wrong. If it was timing you would hear pistons hitting the valves, that sound is very distinct.

 

What do you suspect then? My friends G doesn’t make this sound he’s using a different brand of oil/filter.

 

I am 99% certain it is your starter pinion one way clutch.
This is located in the gear that contacts the flywheel when starting the car.

When the engine starts to idle on its own, for a moment the starter is still mechanically connected to the flywheel and it overs spins the starter gear, BUT since the "one way" clutch is there, the gear on the starter spins faster BUT it does not drive the starter motor. The torque can only move "one way", from the starter to the flywheel.

Why is it making sound?
Over time, the grease dries out.

What is the fix?
Simply remove the starter, (only simple if rear wheel drive) take it apart, clean and re-lube the overrun clutch.
-OR- just put up with it - you are not damaging anything and you will find the sound will come and go
-OR- buy a new starter.

It's item #15.

 

Jeez the starter is $500 from the dealer?!?! I think i’ll put up with it since I’m not damaging anything. I will eventually replace it though most likely with something aftermarket.

 

+1 for the starter pinion/clutch assembly.
A reputable auto shop can typically rebuild your starter within a few hours at a fraction of the cost for a "new" one.

 

Is there a DIY thread for the starter? My G37 is RWD

 

I haven't seen one.

However, this is how I removed the starter on my RWD sedan:
• put the front of the car on jack stands
• disconnect the battery
• remove the front belly pan
• remove the front left wheel (gives a small window of access to the starter to move it or see it)
• disconnect the electrical connections to the starter
• unbolt the starter
• disconnect the the wire that runs to the AC compressor and move it out of the way
• (this part is like a logic puzzle) move the starter to the front of the car by rotating it as needed to move it forward.

There is *JUST* enough room to get the starter out this way, but it will test your patience.
Good luck!

 

I started having this issue as well. Not sure what the cause is. Some days it happens, some days it doesn’t. Subbed though.

 

My 2013 g37 makes the same exact noise on cold starts. It used to stop after 5-10 seconds but now it’s more like 45 seconds to a minute. Been askin around about this for months and gettin nowhere. Of course Infiniti tells me they all do it and nothing to worry about.
I say BULLS?&? Why is it gettin worse if it’s nothing.
My wife and I have loved all of our Infinitis but this one issue has got me wondering if they may be slacking off with their engines. This was supposed to be the Mack daddy of motors when it came out. I was thinkin maybe valves. I don’t believe anybody here has it nailed down yet either except maybe the starter deal. I’m gonna check that one out. Now I’m havin other issues too and it’s goin in for service tomorrow so I’ll ask some techs and see what kinda response I get. I’ll bet the loaner doesn’t make the noise. Oh yeah...
just hit a small post in front of a gas pump moving slower than I walk. Wrinkled the front bumper/facia. No other noticeable damage. Estimate at the body shop that did the work was $2,100.00. I figured I could do it myself for around $1,100. I’ve done body work a lot more complicated before. Total on the bill was $4,900.00. LOL They are right down the block from the dealership AND a State Farm “partner” shop. Hmmmm
My deductible is $250 so big deal right? But I’m thinkin
FRAUD. Parts listed that were NOT replaced etc. etc.
Sorry for the rant but...hey...WTF???

 

weirdest thing happened yesterday... I got a muffler delete and the starter noise went away

 

Maybe exhaust piping was rubbing on it when cold and when warmed up.the exhaust hangers loosened up enough not to rub