Corolla S Rough Idle - Toyota Nation Forum : Toyota Car and Truck Forums

WindyCityPilot · 09-29-2010, 09:38 AM

Within the past few hundred miles I've been noticing that while sitting at a stop light with the transmission in drive the idle is rough.

Here is what seems to happen.

When you come to a stop at a light the idle is around 620-640 rpm's....this is just a guess based on the tach...the tach is a hair above 600 rpm's. The idle at this point is silky smooth. You don't even know the engine is running. Then after about 5 seconds the idle drops to ~600 rpm's and the roughness starts. It's more an annoyance than anything. The car is not going to stall out...it's just rough and you can feel the engine vibrations. If I put the transmission into neutral the rpm's rise to around 620-640 again and the roughness goes away.

The first 2500 miles the car did not do this at all...it was smooth all the time....whether it was in gear or not.

Does anyone else have this problem?

Anyone know what the idle speed should be while in gear? Or if the dealer could adjust this? All it really needs is another 20-40 rpm's (based on looking at the tach) to smooth it out.

***FlawedLegacy*** · 09-29-2010, 09:46 AM

is this a manual or auto??

Dealership should be able to adjust it for you i'd think, but SHOULD being the key word there.

thewalrus2010 · 09-29-2010, 10:52 AM

Idle is adjustable, should be covered under customer satisfaction so it wont cost you anything either.

WindyCityPilot · 09-29-2010, 11:47 AM

Awesome guys thanks. It's an automatic...which just goes to show me I should have got the manual!

I'll schedule an appointment and see what they say.

***SuperchargedMR2*** · 09-30-2010, 12:50 AM

Quote:

Originally Posted by WindyCityPilot

Awesome guys thanks. It's an automatic...which just goes to show me I should have got the manual!

I'll schedule an appointment and see what they say.

Always get the manual.....FTW.

theycmerollin · 09-30-2010, 05:15 AM

It's simple a matter of adjusting the idle screw.

Takes about all of 10 seconds to do this.

thewalrus2010 · 09-30-2010, 09:22 AM

Quote:

Originally Posted by theycmerollin

It's simple a matter of adjusting the idle screw.

Takes about all of 10 seconds to do this.

Incorrect, you need techstream to adjust the idle. No car that I know of since the introduction of TBW has had a manually adjustable throttle.

WindyCityPilot · 09-30-2010, 01:16 PM

Thanks again guys...I'll get it in to the dealer and see what they can do. And Supercharged...yeah yeah yeah I know....

I was close to getting the 5 speed but with as much time as I spend in Chicago traffic I decided to go with the automatic.

***SuperchargedMR2*** · 09-30-2010, 11:04 PM

Quote:

Originally Posted by WindyCityPilot

Thanks again guys...I'll get it in to the dealer and see what they can do. And Supercharged...yeah yeah yeah I know....

I was close to getting the 5 speed but with as much time as I spend in Chicago traffic I decided to go with the automatic.

I drove a 5-speed even in LA traffic for years!

theycmerollin · 10-01-2010, 08:53 AM

Quote:

Originally Posted by thewalrus2010

Incorrect, you need techstream to adjust the idle. No car that I know of since the introduction of TBW has had a manually adjustable throttle.

I stand corrected!

I'm thinking of my 90's model Corolla where it's just a matter of using a flat head screw driver to adjust the idle.

thewalrus2010 · 10-01-2010, 10:48 AM

Quote:

Originally Posted by theycmerollin

I stand corrected!

I'm thinking of my 90's model Corolla where it's just a matter of using a flat head screw driver to adjust the idle.

Damn Straight! JK, cars these days...

RollaRed · 10-02-2010, 10:11 AM

Quote:

Originally Posted by SuperchargedMR2

I drove a 5-speed even in LA traffic for years!

Respect!!! I was born and raised in LA so i know how bad traffic is!

WindyCityPilot · 10-20-2010, 08:57 AM

Took in my Corolla this morning to the dealership to have them checkout the rough idle I am experiencing. Of course it was the standard "can not duplicate problem" and also that even if there was a problem there is no way to adjust the idle speed. I love incompetence at the dealership.

For all you Corolla owners with the 1.8L and an automatic transmission....when you sit at a red light with the car in gear and the headlights, radio, defroster, A/C, and fan off what is your idle speed? The reason I say with all these things off is because when I turn on the headlights or A/C for example the idle speed rises by almost 200 RPMs. When everything is off and come to s stop the idle initially is at about 650 which is where it should be at....then after about 5 seconds it creeps down to ~600 RPMs and the idle becomes rough. If I turn on the fan to the highest setting the idle will go below 600 RPMs and not recover at all.

Anyone know of a dealer in the Chicago area that is staffed by techs that know what they're doing and actually take the time to investigate the problem?

msncorolla422 · 10-20-2010, 12:49 PM

mine stays right in the middle of 0 and 1 w/out the a/c and goes to 1900 when the a/c is one but it fluctuates which is normal because you can here the fan turn on and stuff

cu2cool · 10-20-2010, 11:30 PM

WindyCityPilot, you're not the only one with this problem. I get it on my 09' Corolla as well. Only when I am idle for a long time in Drive position. I think it happens randomly though. There are times when I idle in Drive for a while, but the RPM doesn't drop to ~600rpm.