I have had a couple incidents with my '03 G where the RPM's bottom out and my car completely shuts off. It only seems to happen when I'm driving on the interstate, slow down a bit to get off at an exit, and push in the clutch. The needle falls quickly to the bottom on the RPM gauge and the car shuts off. It doesn't happen every time, but I haven't noticed a difference in anything that I do from when it shuts off and when it doesn't.

Anyone else ever have this problem? If so, how did you fix it?! Thanks

 

i read problems where it was the air fuel ratio, did you get a cai recently installed, that might be your problem.

 

It has a z-tube installed by the previous owner, but no cai as far as I know.

 

i'd try resetting the ecu,

http://www.nicoclub.com/archives/g35...-learning.html

 

I would also try cleaning your Mass Air Flow sensor (MAF). You can buy MAF Cleaner at any autoparts store. Please be sure to only use MAF Cleaner, no other kind!

 

Check for vacuum leaks, any cracked hoses, etc. Replace PCV valve. Also try the link jenxin posted to relearn idle air, and valve close position learning.

 

My rpm's used to drop unusually low as well when disengaging the clutch, seemed to happen more often when I had the AC on as well. Not too long ago, I got a CEL indicating a malfunction with the A/F ratio. I took out my intake box, recharged my K&N filter, cleaned all intake parts, and also cleaned my MAF sensor with MAF cleaner. I cleared the code, and it hasn't come back. Also, my rpm's do not dip as severely anymore.

To make a long story short, +1 to what Scoobyroo said!