I think your right... I assume it was 200 rpm increments but I took closer look and it has big gap from 0 rpm and first line...
So my car idle at 650... oops... sorry for confusion...

 

I guess I fell into that trap as well. I thought each increment was 200 rpm, but if that first tick is 500 rpm, then my idle would also be around 650 as well. I guess now...why would my car at "warm" startup wants to "die"?? It's that same ideal where people where putting it in neutral and all of a sudden the tach would go all the way down to zero, and the car would die. I'm almost tempted to put the stock air box back on to see if the popcharger is the culprit. Any clues??

 

BUMP!
ok the pic below
i took this picture when i bought my new z
idle looks normal
but after 2 years of driving..
my idle sit arounds 300~400 rpm?
the red line i drew is where my idle is. ( nothing to do with X mark)
i have cleaned TB, cleaned MAF, checked vac leak( no leak)
when i turn my AC idle jumps to 950rpm sometimes 900rpm
could it be the Alternator? spark plug?
my 2008 z is bone stock, 36k miles
changed new clutch and flywheel under warrenty ( i can still hear chattering.. i thought they swapped my bearing but no?)
btw my z jerks while deceleration in 1st and 2nd gear
sometimes 3rd.

 

~750, no grounding kit.

 

i have the same issue for the pass couple days. i was at a stop light n my rpm went that low and stalled on me. i turned it back on and stalled again. so i just rev the engine to 1k when i'm at a stop. umm this started when i installed my TP's few days ago.

 

That makes no sense to me. I would think ALL lines represent 250 RPM. You have 3 lines between ALL other RPM readings equally spaced in 250 RPM increments. Why would they be different for the 1st 1000RPM? Yes they're spaced differently below 1000RPM, but that's because very LOW rpms aren't that accurate.

In this pic it looks like the needle is at
650-700 RPM and the red mark is at 375ish.

 

950rpm idle

 

I idle between 875-925 (cams got me by the *****), just depends where I set it at. Prior to the turbo setup about 650-700ish and after the stock block turbo setup about 750-800ish.

 

OP needs to do the idle re leearn ecu reset, thats all.
Groudning kit has little to do w it i suspect.. google search technosquare 350z ecu reset.
USE A STOP WATCH. guessing or counting 1-1000 will not work.

 

I have done these learning for all of them, you don't need a stop watch, a good 1000 count worked fine

 

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