Possible issue with cold idle?

Zenogias

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Hey all,

I noticed recently that when my 2023 Performance Z is cold, it has an slightly unstable idle. It's nothing crazy but bounces between 1150-1250 rpms. I know I am probably just being paranoid, but I never noticed this until around the 1800 miles mark right after I took the car into the shop for some very minor body work. It's possible it was always like that, and I just didn't notice until recently, so I'm hoping I could get some feedback from fellow owners.

Is this normal? Does yours idle like this on a cold start? It does significantly reduce once warmed up, mostly staying at 700rpm but sometimes will bounce between 700-650rpm.

Thanks for taking a look!

 
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TheRoyalStig

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Just wanted to say hell yea to a Xenogears fan.

Sorry I have no answers to your actual question.
 
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Racebox

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Normal!
When the car cold starts it has to heat the o2 sensors and cat.
It goes into a cat heating mode which retards timing and it is roughly aiming for fuel as O2’s arent reading and it’s not in closed loop fuel yet. That takes about 5-10 seconds. The car then settles down in closed loop on a standard cold start.
 
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Zenogias

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Normal!
When the car cold starts it has to heat the o2 sensors and cat.
It goes into a cat heating mode which retards timing and it is roughly aiming for fuel as O2’s arent reading and it’s not in closed loop fuel yet. That takes about 5-10 seconds. The car then settles down in closed loop on a standard cold start.
Appreciate the response! It takes longer than 5-10 seconds for mine to normalize (I'll pay close attention next time, but I think it's about 30 seconds to a minute), but I'm in the pacific northwest and it's a bit cold up here right now. Thanks for taking the time, makes me feel a lot better hearing this from someone who knows what they are talking about.
 

Mr&Mrs

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To add to racebox reply. I've also noticed jumps in rpms on various cars when the a/c compressor turns on or off. Even turning the steering wheel can add extra stress and increase idle. All perfectly normal. This has been even more common on a couple of my Nissans over the years.
 

BigBlue

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I experience this to and find that it varies with the OAT
 
 





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