Idle speed

[masher]

I have a 2010 corolla s, I bought it new 3 weeks ago.
I find that the idle fluctuates from 700 to 900rpm.
When the car is at it's lowest you can feel the engine running, but in the higher range it feels so smooth you can barely tell it's on.
At a stop it will rest at around 900 then seconds later it will go down to lower rpms(600-700) and sometimes jump up again.I know the computer adjusts the motor constantly,but I'm just curious about this.
Is this normal?.

[djb383]

A/C compressor cycling on/off?????

[masher]

Actually it feels as if it was,but the lights on the controls not lit up and it's been chilly enough that I have not even tried the ac out yet.
I just went out tried out the ac, it's working and I don't think that's it.
All other vehicles I've had or driven the idle sits in one spot.
Where do your idle speeds sit?,does it vary?.

[HarleyCVO]

Originally Posted by masher

Actually it feels as if it was,but the lights on the controls not lit up and it's been chilly enough that I have not even tried the ac out yet.
I just went out tried out the ac, it's working and I don't think that's it.
All other vehicles I've had or driven the idle sits in one spot.
Where do your idle speeds sit?,does it vary?.

Could be your defrost on if not the a/c.
Using the defrost kicks on the compressor causing a power surge

[ZenithTheTV]

If you have the dial set to defrost, like air to the windows, or even windows and feet it'll automatically have the AC on, even though the light is off.

But an idle around the range you stated is normal.

[danakin]

Mine idles in that range, wouldn't think much of it. My 1990 Celica idled anywhere between 600 and 2000, so I don't really notice 200rpm difference.

[metalbones]

Originally Posted by masher

I have a 2010 corolla s, I bought it new 3 weeks ago.
I find that the idle fluctuates from 700 to 900rpm.
When the car is at it's lowest you can feel the engine running, but in the higher range it feels so smooth you can barely tell it's on.
At a stop it will rest at around 900 then seconds later it will go down to lower rpms(600-700) and sometimes jump up again.I know the computer adjusts the motor constantly,but I'm just curious about this.
Is this normal?.

My car idles within the same range, I have a 2009 S. I was concerned about the fluctuation but after getting another opinion I realized it was paranoid about new car issues. I feel it when it idles low but do not the higher it is and this idle change occurs with or without the A/C or defroster. Sit back and enjoy the car.

Originally Posted by danakin

Mine idles in that range, wouldn't think much of it. My 1990 Celica idled anywhere between 600 and 2000, so I don't really notice 200rpm difference.

On another note, my first car was a 1989 Honda Accord LX which was carbureted. My car was idling very low (400rpm) so I decided to try and adjust it with the help of my friend's father. He adjusted the idle screw a bit and it seemed alright right then. I noticed that on a cold start it would idle too high, around 1500rpm, until it warmed up. Well I decided to adjust it myself. I start to loosen the screw (wrong way to turn it for my problem) and I hear the telltale "plink" of a screw falling. It never came out of the abyss in which it fell despite my rocking and searching for it.

From then on my car idled at 3000rpm on a cold start and 2000rpm when hot. It was an automatic so putting it into gear was fun and I would knock it into neutral at stop lights just to avoid fighting the motion with the brakes but people thought I wanted to race.

I traded it a few months later for $500, hahaha. I miss that car.

[masher]

Originally Posted by metalbones

My car idles within the same range, I have a 2009 S. I was concerned about the fluctuation but after getting another opinion I realized it was paranoid about new car issues. I feel it when it idles low but do not the higher it is and this idle change occurs with or without the A/C or defroster. Sit back and enjoy the car.

Thanks,now I'll try not to keep my eyes on the tach at stop lights.