I’ve posted here before about my 09 G37 7AT having an issue where the RPMs drop when I let off the throttle, then bounce back slightly and give a tiny kick. I can somewhat hear a vibration noise when the rpms are coming back up again, it starts quiet and then louder as it rises and of course completely stops once it’s back to normal. I also rarely feel a small vibration at low speeds. It mostly happens during slow driving or on slight uphills.

Here’s everything I’ve already done: • New spark plugs • New ignition coils • Fixed an exhaust leak • Cleaned the throttle body • Replaced a cracked air intake pipe (helped but didn’t fully fix it) • Completed the idle relearn procedure

Still no CEL and no codes.

The issue has improved but still shows up in the same situations. Anyone with a G37/VQ37 or 7AT run into this before?

 

Im not sure how to work the forums BUT I had the same issue, but fixed now. I replaced all that you’ve replaced but I have KNN Short ram intakes and I didn’t plug my vacuum hose back into place on the cold air intakes, once I did that my rpm’s stayed at idle range 600-700rpms steady and didn’t drop below like they used to! I hope this helps. Also the vacuum hose is located under both cold air intakes, after the filters before the throttle body. (Close to coils on both sides)

 

Ever figure it out?

 

I was having same issue. Was my fuel pump.