Have about 6000 wonderful miles on the G-unit so far.. love it!

Just a quick question for some of you that may have the same issue...

Every 4th or 5th startup (particularly in the cold outdoor weather when the car's engine is cold > 2 hours) I'll start her up and after about 6-8 seconds .. (once started, and it starts flawlessly) I hear a rather loud "pop"/"bang" almost like the sound of someone taking a heavy hardbound book and dropping it flat on the ground from 10 feet. I don't perceive this in the steering or footwell, it's heard, not felt.

The car otherwise drives fine, and I'm just curious what it is, if anything -- a warm engine start doesn't reproduce this symptom.

Thanks in advance and happy motoring

 

Puzzling... Take it to the dealer for sure. First take it to a regular shop. They'll probably find something before the dealer.

 

I'd guess that the engine is starting rich and may be building up some vapor in the exhaust. Once the motor is lit, it only takes a few moments to get the exhaust hot enough to set off this unburned fuel. Nothing to worry about, but I bet it's a BEAR to reproduce!

 

what type of oil have you replaced it with? also, where are you located?

 

I'm in chicago --

just had an oil change with synthetic (not the super expensive stuff that's "recommended" for the VQ engines).

Thanks for the replies -- will be conferring with the stealership next oil change...

 

Peter,
I would definitely take in to the dealer. You and I purchased our G37's at the same place, and I have to tell you that my recent problem with a Warm Start issue was resolved in full by them. It was something I expected to argue with them about, because it only happened after 2 hours of resting and always started, albeit slowly. To my delight, they duplicated the problem and worked diligently to fix it. All under warranty and with a loaner. It took 2 trips and about 1.5 weeks at the dealer, but they identified the problem and needed to wait until the injectors arrived to fix it. Your's sounds like a different problem, but you can mention the "warm start" issue to Drew in Service and he'll know the car (mine) that you're talking about. I just picked it up 2 weeks ago.

Search for the thread with my name to find a few more details of the problem I had. Drew said that Nissan (Infiniti) was very interested to get my injectors back to R&D to find out what caused them to leak.
Dave

 

Hi Dave,

Good to hear from you -- thanks for the tip -- I'll definitely let them know about your experience, perhaps there's some correlation.

What exactly did you experience with the warm start?

Thanks

 

I've had the same issue with my 2009 G37xS. I'll let them take a look at it while i get my 7AT tranny re-programmed via the TSB.

 

Hi PeterUbers,

I've had customers in town all week and haven't logged in here since I last posted. The car is still starting normally after 3 weeks, so they definitely fixed the problem. I described the problem pretty well here:
https://www.myg37.com/forums/g37-sed...art-issue.html

Good luck and let us know if they find anything.

Dave