[QUOTE=llebcire;4256555]Thanks for the update!

What I'm taking from this is the idle drop is somewhat normal, and the vibration was reduced with an idle re-learn and flash?

Does the G not have adaptive engine mounts? My Accord had active engine mounts that were designed to minimize vibration - maybe the lack of something similar on our cars is why we can feel vibrations?


HI ERIC,
AS OF RIGHT NOW, YES, THIS IS MY TAKE-AWAY AS WELL. IF I WERE TO GUESS, THE RE-FLASH CORRECTED THE GLITCHY TB OPERATION SIMPLY BY RE-LOADING THE SOFTWARE (AND ANY UPDATES) INTO THE ECM. SINCE THIS VEHICLE IS THE NEWEST OF THE ENTIRE LINE (2015) I'M FIGURING I ALREADY HAD THE MOST UP-TO-DATE SOFTWARE. BUT, YOU NEVER KNOW...

I'M NOT SURE WHAT TYPE OF ENGINE AND/OR TRANNY MOUNTS ARE USED ON THE G. I'M SURE AN INFINITI TECHNICIAN COULD ANSWER THAT QUESTION.

 

Thanks for the updates, I was really hoping to hear a solution. Have you change spark plugs or coils by any chance ??

 

Yeah, I was hoping for a solution as well. However, I kinda had this feeling it wasn't going to be totally solved. No, I haven't changed any plugs or coils. I don't think this quirk is going to be solved due to performing a maintenance-type issue. Besides, if there was an issue with a plug or pack, it would've easily shown a disparity on the diagnostic test.

I think the ECM reprogram and idle relearn (via CONSULT method) helped in getting all the electronically-actuated mechanical devices working correctly and in sync again. As they mentioned, I did have a TB that seemed to be acting funny. I think overall, what I have now is most likely considered "normal operation" for this type of car. However, I am thinking of taking this back to the dealer to have them set the idle to 700 or so to see if that bumps-up the RPM's while in Drive.

 

UPDATE #2: 10-1-19

It has been a week and three days since my service. I am beginning to notice more vibration when at a stop in D. It is not all the time. Sometimes it is not noticeable, while other times it is very prominent. During the times it is very prominent, I will turn off the A/C (not the entire system, I just push the A/C button off) then push the button back on again. The RPM's rise above 500 to around 650 or so, and the vibration greatly reduces. Sometimes I think it may be A/C compressor related, but, the vibration is still there (though not as much) when the HVAC system is totally off.

Basically, this is starting to drive me nuts... What the heck is causing this? I have a feeling it's either something super-trifling (like the washer fluid reservoir cabin noise) or something huge (like bad TB's, ECM etc...).

What's really interesting is that there are G's out there that have never had any problems whatsoever with this issue. Then, there are others that are plagued by it and cannot find the solution. I wonder if this problem relates to a specific production cycle? Those of you with the issue, what year is your car? Also, does this problem occur more with AWD vs. RWD models? Does it occur more with sedans vs. coupes?

 

2013 g37x sedan with 86k n have the very same issues as mentioned above.

 

2012 G37xs Sedan 7AT 76K, and I too have noticed these exact behaviors. It doesn't happen often, very sporadic and the only common symptom is the 500rpm idling at stop lights. I've been running TorquePro hoping to see an anomaly whenever it does occur, but it's difficult since I can go a week without an incident occuring. The determination in this thread to find the source is definitely appreciated.

 

I get it sometimes. Maybe once a month? Ill blip the throttle as it happens and it goes away.
2012xS sedan w/65k Torque doesn't show any wierd correlations like a afr, maf, or timing adv change. Though Id really have to sit down in R-studio to run the real statistics.

 

2011 G37x Sedan
Production 10/28/2010

-Eric

Here's a video from Friday where the idle was correct without the A/C after spirited driving.

You Tube

 

Wonder if your throttle body is having a sensor issue which is sporadic like this. Do you have access to throttle bodies you can borrow?

 

Nothing I can borrow. There is a salvage yard near me that has both TB's off of a 2014 Q60... $40 each.

UPDATE:
I'm planning on going to a friend's house this weekend to install an OEM rear deck wing. While there, we're gonna go to his shop and put my car up on the lift. It's a demolition business so it's a ramp lift for servicing construction vehicles (i.e. dump trucks, etc.) With one of us in the car, and the car ON and in Drive (D) with foot on the brake, the other will check out underneath to see if anything can be seen, felt or heard when switching throughout the gears.

 

UPDATE:
I didn't get the chance to get my car on the lift this weekend. Most of the time was spent getting the spoiler placed on the trunk. By the time we were finished, it was time to meet up with out wives for dinner.

However, I received a follow-up call from the Infiniti dealer late Friday afternoon (9-4-19). She was calling to see if everything was ok since the service. I advised the issue is still there and explained it seemed to be ok at first, but now it has returned. I also advised that the RPM's pretty much went back to 500 as soon as I left the dealership. I then proceeded to explain that there are a host of other G' owner's that are experiencing the same exact conditions; and that we have all tried the host of possible solutions but still no resolution. I asked her to ask the technician if the RPM's can be set to a minimum of 700 using the CONSULT in an effort to see if that will keep the RPM's raised when in Drive (D). I also advised it is unknown if this ultimately is an electronic or mechanical issue. She said she will speak with the service manager and the technician about my follow-up and give me a callback next week (which should be this week sometime).

I'll keep everyone posted.

 

You SIR, are the man.

 

UPDATE:
I called the dealer yesterday (10-12-19) since I hadn't received a callback from my conversation with adviser Shauna on 10-4-19. She said she spoke with the service manager (via phone as he was not at the dealer) and he said they would NOT set my base idle to 700 or higher as it would void any warranties, as well as fall outside the scope of Infiniti's specifications for the vehicle. I was ticked at this point! She added that all I could do is possibly find another Nissan/Infiniti dealer that would perform this service--indicating that it would seem this dealer would not do it, but there might be another that would.

I thanked her for the info and the call ended. Shortly afterwards, something dawned on me and I called her back. I advised her that the Infiniti specification for base idle is in fact 650 RPM +/- 50. Therefore, the range that idle can be set is 600-700 RPM. I told her than that me requesting an idle set to 700 is well within the Infiniti specifications. She advised I would need to speak directly with the service manager regarding this. I advised her to leave a note with the service manager with this info, and have him call me next week when he is in the shop.

As always, I'll keep you updated.

 

Sh*t, I feel like there wont be an answer, like we're just stuck with this idle issue. SMH. And as always thanks for the continued updates, you the man.

 

I appreciate all of the effort as well, however with a vehicle that's been out of production for several years I'm not holding my breath for assistance from Infiniti. If this was a larger issue, such as safety or the galley gasket, I could see a TSB, warranty extension, class action, etc. Our situation is really more of a nuisance than anything.

-Eric