Low idle means you probably need to clean the throttle body.

 

That was my first thought too so I cleaned the throttle body and mass air flow sensor and it still does it

 

Many cars do this as a normal thing. It adjusts to the load but there may be nothing wrong.

 

My 2010 Corolla Auto does the same thing. I think that the cpu is programmed to increase the idle rpm when the a/c and/or the head light is turned on.
My observation when the car is fully warned up is:
a) Foot on Brake and gear on Drive, idle = about 600 rpm
b) Foot on Brake and gear on Neutral, idle = about 700 rpm
c) As (a) plus a/c or light turning ON, idle = about 800 rpm
d) As (b) plus a/c or light turning ON, idle = about 800 rpm

 

I have a 2010 corolla base model and ive been noticing the same thing. When im at a red like in drive foot on the brake the rpms drop to 600. Is that normal or sjould I have it checked? Its a rough idle

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2010 corolla le

 

Hi, just registered, to say i have the same problem, i have cleaned the thottle body, and didn't fix it.
Today i notice if i turn on the lights stopping in a red light, the idle when from 600 to 800 rpm, and the car run smooth.

 

Same problem with mine

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My 2010 Corolla Auto does the same thing.
I think that the cpu is programmed to increase the idle rpm when the a/c and/or the head light is turned on.
My observation when the car is fully warned up is:
a) Foot on Brake and gear on Drive, idle = about 600 rpm
b) Foot on Brake and gear on Neutral, idle = about 700 rpm
c) As (a) plus a/c or light turning ON, idle = about 800 rpm
d) As (b) plus a/c or light turning ON, idle = about 800 rpm

It seems to me the designer for this 2010 auto model fails to maintain the idle speed to a satisfaction range because the cpu could be programmed for such purpose and the idle speed could be programmed for any rpm if the designer likes.

For condition (a), 600 rpm is a bit too low because it will be at the critical stable rpm. 650-700 rpm would be a better option which is the same rpm at conditon (b).
The rpm for (c) and (d) should be slightly lower, say 700-750 rpm.

 

So there is no way to change or fix this rough idle???

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I figured out why I had the rough idle in my 2010 corolla. I work at pepboys and I had my battery checked and my battery and alternator was fine. The cold crank amps were at 413 which is low. OE recommended is 355 which is really low so I decided to change my battery. I purchased the bosh battery with 640 cold crank amps and the rough idle has stopped. For now atleast I dont feel it.

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I figured out why I had the rough idle in my 2010 corolla. I work at pepboys and I had my battery checked and my battery and alternator was fine. The cold crank amps were at 413 which is low. OE recommended is 355 which is really low so I decided to change my battery. I purchased the bosh battery with 640 cold crank amps and the rough idle has stopped. For now atleast I dont feel it.

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When did you install the bosh battery and how much is it?

 

I purchased the bosch battery today its 124.99 before tax at pepboys it has 640 crank amps which is good. After installed u have to drive it to relearn the computer. As I drove it the rpms were at 800 with my lights off no rough idle. Im driving now and the rough idle is back. Sorry I guess the computer relearned and its back to square one.

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So it is the poor design of Corolla. Unless Corolla reprograms or a new cpu, there seems there is no way to deal this rough idle.

 

It is not likely the battery it is the fact you disconnected the battery. It will likely be the same after a while. If you have cleaned the throttle body and thats not it then it would likely be fuel injectors. How many miles do you have? when was the last time you ran a fuel injection cleaner? You can try the Chevron Techron concentrate or the Redline SI1 or a can of BG44K. This should be run at least every 30k miles or so.

 

What model/year of Cororlla do you have?

 

09 corolla low idle problem when stopping.

I have 09 corolla and just noticed that i am having low idle when stopped on red light or stop sign. rpm is around 500 and car is shaking . once turn on AC or headlights, it goes 707-750 and shaking stops. I searched many forums but still no solution to the prblem.I get TB cleaned last week since it is told to be causing vibration. Any solution?Thanks

 

I have 09 corolla and just noticed that i am having low idle when stopped on red light or stop sign. rpm is around 500 and car is shaking . once turn on AC or headlights, it goes 707-750 and shaking stops. I searched many forums but still no solution to the prblem.I get TB cleaned last week since it is told to be causing vibration. Any solution?Thanks

Did you buy this car new? Did it do it when it was newer? I have a 2013 Corolla that has 21,000 miles that I bought used and has the same low idle issue off and on when sitting at a stop light. It dips to 600 and stays there for the whole red light. It makes the steering wheel vibrate and later in the day when it has been driven all day off/on and traffic is bad, it even makes my butt vibrate. I know some people say it's "normal", but to me that seems like quite a bit of vibration and would think as the car gets older, all this vibration isn't good for old seals, bushings-anything made out of rubber. To my astonishment, cars have a lot of rubber. I wanted to keep this car as long as I kept the old Corolla, 17 years, without having to replace things prematurely. The old Corolla didn't start having any vibration issues til its 17th year of life.

Anyway, I have been googling this off and on for a few months and found one guy who had what everyone kept saying was normal something or other(not a low idle issue like us). He encouraged people to call Toyota of North America and I don't know if he got enough people to call and complain, but at the end of the thread someone reported that Toyota put out a technical service bulletin for it. I wonder if we could get enough people calling if something could be done. I pm'ed one guy who had complained about the same issue on here awhile back and he said he had called "Toyota Japan" and would let me know what they said. He seemed really upset.

 

Rough Idle 2010 Corolla

I just ran across this thread because I recently got a 2010 Corolla LE. 150K car runs perfect no issues what so ever beside this rough idle every one is talking about. The car will all most idle to a complete turn off at a sudden stop like stopping at a red light. By mistake I was riding around one day and turned on the lights and noticed the low idle had completely stop'ed. Turned them off and the car all most cut off at the next red light. This is the same with the A/C on and off. I changed the plugs and cleaned the throttle body. Same thing, I now drive with my head lights on with no issues but this is really bugging me!! I'm pretty good at fixing car problems and this has me stumped! Even had the battery checked. Could this be a bad voltage regulator? or alternator problem? I have no dummy lights on in my dash. Since the Throttle Body is completely electronic could that be the problem? I doubt its fuel injectors because it would do it with or with out the lights on. Plug Wires? It has to be something electrical I would think. Is there a burned fuse we are all over looking? Any Help Is Appreciated!!!

P.S If I fined the problem I will post here ASAP

Thanks, Lonnie

 

I just ran across this thread because I recently got a 2010 Corolla LE. 150K car runs perfect no issues what so ever beside this rough idle every one is talking about. The car will all most idle to a complete turn off at a sudden stop like stopping at a red light. By mistake I was riding around one day and turned on the lights and noticed the low idle had completely stop'ed. Turned them off and the car all most cut off at the next red light. This is the same with the A/C on and off. I changed the plugs and cleaned the throttle body. Same thing, I now drive with my head lights on with no issues but this is really bugging me!! I'm pretty good at fixing car problems and this has me stumped! Even had the battery checked. Could this be a bad voltage regulator? or alternator problem? I have no dummy lights on in my dash. Since the Throttle Body is completely electronic could that be the problem? I doubt its fuel injectors because it would do it with or with out the lights on. Plug Wires? It has to be something electrical I would think. Is there a burned fuse we are all over looking? Any Help Is Appreciated!!!

P.S If I fined the problem I will post here ASAP

Thanks, Lonnie

My 2010 Corolla Auto does the same thing.
I think that the cpu is programmed to increase the idle rpm when the a/c and/or the head light is turned on.
My observation when the car is fully warned up is:
a) Foot on Brake and gear on Drive, idle = about 600 rpm
b) Foot on Brake and gear on Neutral, idle = about 700 rpm
c) As (a) plus a/c or light turning ON, idle = about 800 rpm
d) As (b) plus a/c or light turning ON, idle = about 800 rpm

It seems to me the designer for this 2010 auto model fails to maintain the idle speed to a satisfaction range because the cpu could be programmed for such purpose and the idle speed could be programmed for any rpm if the designer likes.

For condition (a), 600 rpm is a bit too low because it will be at the critical stable rpm. 650-700 rpm would be a better option which is the same rpm at conditon (b).
The rpm for (c) and (d) should be slightly lower, say 700-750 rpm.

Please refer to this previous post of mine, it seems that this is a design fault in the cpu. Unless Toyota reprogrammes or changes the cpu, there is no way to solve this rough idling.

 

My wifes 09 Corolla did this too.
I put Lucas fuel injector cleaner/upper cylinder lube in every fill up which made it idle normal again. 3 OZ per 10 gallons.
If the car misses a couple Lucas treatments it starts idling rough again.

 

If this is the case it may be a fuel injector issue. I've noticed a sulfur smell sometimes and on the rare occasion not so smooth acceleration and not so smooth idle even with the lights on. I'm gonna try this too and see what happens. I'll report back the results!

 

I had the same problem. Replace the belt tensioner and belt problem solved. I was puzzled to. actually for about three years but today that fixed my problem same as you describe

 

Had this same issue, found out one of my ignition coil is bad. I bet u, one of the cylinders is not firing well due to weak/bad coil or plug. Ask mechanic to troubleshoot the faulty coils or plugs and thank me later

 

I had my car repaired at a bodyshop and it stayed parked for months. Right after that it idled rougher, so I got the plugs changed, but the low idle with headlights closed was always there (from KM 0)

Put things in perspective : 600rpm is still A LOT . thats 10 turns per second. 4 cylinders are unbalanced by design, its not a V6 or V8 engine, it will shake.