So when its 45-50 degrees here in TX(or even lower than 45 degrees), I start the car, go to school(10 min drive), and when i notice sometimes when i get to a stop my RPM will drop somtimes to 600-500 slowly then have this little "pump" as if air went through trying to breathe going back to 650-700 RPM
(car doesn't really vibrate that much when it happens) when i have my foot on the brake, I do feel this little "Pump" when the RPM goes up to 650-700 RPM coming from 600-500 RPM

The car runs just fine when driving, Normal RPM's when driving (only 129k miles on the car) its just when I come to a stop on cold days, this RPM thing happens. thats it.

But the other thing is when its a WARM day, lets say 65+ degrees, When i come to a stop, my RPM will NOT drop at all, stays around 650-700 RPM and stays like that for the whole driving time. and everything looks fine.

My guess is that when its cold, The car needs time to warm up, making the RPM drop to 600-500 RPM on stops (ME being in the car only for 10-13 mins just to get to school)

any thoughts u guys might have? In my opinion it could be my MAF reacting to cold weathers or such? and needs to warm up to have that normal reaction so it stops the RPM drops on stops during cold days?

My guess.. but what do yall have to say?

 

anyone know?

 

Normal.

 

Why is that normal? I want to know. im curious.

 

When it starts up first thing in the morning, does it initially idle between 1500 and 2000?

 

yeh at park when start up it usually does go above 1k+ RPM, If i remember its at 1.2 or 1.3k and then when it gets a bit warm, it'll idle somewhere in the 1k , Btw Car is Stock engine.

It looks all normal to me, but what caught me is when I came to stops and somtimes was doing that 600-500 RPM then pump to 650-700 thing I was saying.