Fluctuating RPM - Toyota Yaris Forums

DenverDave · 01-27-2010, 11:51 AM

After the engine is warmed up and in idle the RPM continuously cycles between 400 and 600. It will be running smooth at 600, then the RPM drops to 400, where it runs rough for a few seconds, then the RPM increases to 600 where it runs smooth for a few seconds, etc. It has done this since the car was new. Is this normal?

Parmas · 01-27-2010, 02:53 PM

What engine do you own?

Could you set the idling to 800-1000. 600rpm seems too low for me

" It has done this since the car was new " Why don't you ask the dealer that sold you the car in the first place?

TheSilkySmooth · 01-27-2010, 03:24 PM

It does this when charging or under load with heater/ ac or radio headlifghts. Normal but suboptimal. AFIK nothing correctable.

PHXDEMON · 01-27-2010, 09:04 PM

It's just how toyota tunes these cars to get as much gas mileage as possible. It is normal.

schleppy · 01-27-2010, 09:34 PM

Normal, mine does it too from time to time.

DenverDave · 01-28-2010, 09:13 AM

OK, I thought it could be normal. It's like the engine is seeking to burn as little gas as possible.

yaris2010RS · 01-28-2010, 09:49 AM

i have posted a similar problem also. mine idles at 500 rpm then will jump to 800rpm (ish) and then drop down. at first thought it was the a/c kicking in so i turned everything off and it still does it. look under the hood and watch, i noticed as soon as it jumps up the rpm the fan will kick in and when it goes back down the fan turns off.....

TheSilkySmooth · 02-05-2010, 02:45 PM

Operating with any partial or Defrost On setting on air director with fan at 1 or higher = AC on; regardless of ac switch on or not. I think.

blacksandiegovitz · 02-06-2010, 12:54 PM

Quote:

Originally Posted by TheSilkySmooth

It does this when charging or under load with heater/ ac or radio headlifghts. Normal but suboptimal. AFIK nothing correctable.

^^ +2

why? · 02-07-2010, 08:53 PM

mine has always done it. it's normal.

sk8manmike · 02-28-2010, 02:47 PM

Mine does this too - exactly how u say. Stays at 600 and then drops to sub 500 rpms, except my car shutters slightly when it does this. Should I up my idle rpm to say, 700?

Nvm i guess you can't since its electronic - guess i just have to live with it :(

01-27-2010, 11:51 AM	#1
DenverDave Drives: 2010 Hatchback Join Date: Jan 2010 Location: Denver Posts: 9	Fluctuating RPM After the engine is warmed up and in idle the RPM continuously cycles between 400 and 600. It will be running smooth at 600, then the RPM drops to 400, where it runs rough for a few seconds, then the RPM increases to 600 where it runs smooth for a few seconds, etc. It has done this since the car was new. Is this normal?

01-28-2010, 09:49 AM	#7
yaris2010RS View User's Garage Drives: no-longer-boosted '10 Yaris Join Date: Nov 2009 Location: Angus, Ontario Posts: 1,891	i have posted a similar problem also. mine idles at 500 rpm then will jump to 800rpm (ish) and then drop down. at first thought it was the a/c kicking in so i turned everything off and it still does it. look under the hood and watch, i noticed as soon as it jumps up the rpm the fan will kick in and when it goes back down the fan turns off..... __________________ If it has boobs or wheels sooner or later your gonna have problems with it

02-07-2010, 08:53 PM	#10
why? Only Happy When it Rains View User's Garage Drives: Yaris LB Join Date: Jan 2006 Location: harnett county NC Posts: 4,097	mine has always done it. it's normal. __________________ Colin Chapman disciple

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01-27-2010, 02:53 PM	#2
Parmas Drives: Vitz RS Turbo Join Date: Nov 2008 Location: ML Posts: 576	What engine do you own? Could you set the idling to 800-1000. 600rpm seems too low for me " It has done this since the car was new " Why don't you ask the dealer that sold you the car in the first place?

01-27-2010, 03:24 PM	#3
TheSilkySmooth Drives: 08 3DR 5M Bayou Blue; 09 Fos Join Date: Oct 2008 Location: New Hampshire Posts: 622	It does this when charging or under load with heater/ ac or radio headlifghts. Normal but suboptimal. AFIK nothing correctable.

01-27-2010, 09:04 PM	#4
PHXDEMON View User's Garage Drives: 2007 Red Liftback Join Date: Oct 2008 Location: Phoenix, AZ Posts: 885	It's just how toyota tunes these cars to get as much gas mileage as possible. It is normal.

01-27-2010, 09:34 PM	#5
schleppy I love momentum. View User's Garage Drives: 2009 Yaris LB, Red Join Date: Feb 2009 Location: Boston, MA Posts: 587	Normal, mine does it too from time to time.

01-28-2010, 09:13 AM	#6
DenverDave Drives: 2010 Hatchback Join Date: Jan 2010 Location: Denver Posts: 9	OK, I thought it could be normal. It's like the engine is seeking to burn as little gas as possible.

02-05-2010, 02:45 PM	#8
TheSilkySmooth Drives: 08 3DR 5M Bayou Blue; 09 Fos Join Date: Oct 2008 Location: New Hampshire Posts: 622	Operating with any partial or Defrost On setting on air director with fan at 1 or higher = AC on; regardless of ac switch on or not. I think.

02-28-2010, 02:47 PM	#11
sk8manmike Drives: 2007 Yaris 4d Sedan Join Date: Feb 2010 Location: CO Posts: 28	Mine does this too - exactly how u say. Stays at 600 and then drops to sub 500 rpms, except my car shutters slightly when it does this. Should I up my idle rpm to say, 700? Nvm i guess you can't since its electronic - guess i just have to live with it :(