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GabL
02-20-2006, 11:38 AM
I just found my car won't shift from 3rd to 4th gear around 3000 rpm in some cases, I kept revving it up to 4000+ rpm THEN it shifted to 4th. Is that normal?

echo_hrs
02-20-2006, 11:53 AM
I just found my car won't shift from 3rd to 4th gear around 3000 rpm in some cases, I kept revving it up to 4000+ rpm THEN it shifted to 4th. Is that normal?

If the engine is cold, and hasn't reached normal operating temperature, the transmission will not shift up into 4th gear. You will find it will rev high in 3rd gear until the engine has time to warm up...

This is a normal feature on Toyotas, and somehow is set up that way to protect the engine during colder temperatures...

Ziv
02-20-2006, 12:38 PM
funny I actually asked the same question to the dealer sometime ago, when I relize both my Yaris and my buddy Celica have the same 'Cold' icon on the display. and yeah, apparently 'overdrive' will only activate when is NOT in 'cold' such 4th gear, 5 gear depends on how many gear your car has. For auto of courze.

GabL
02-20-2006, 01:16 PM
If the engine is cold, and hasn't reached normal operating temperature, the transmission will not shift up into 4th gear. You will find it will rev high in 3rd gear until the engine has time to warm up...

This is a normal feature on Toyotas, and somehow is set up that way to protect the engine during colder temperatures...

That explains it... thanks for the info! So is it better to warm the car until the cold engine oil icon is gone before taking off?

why?
02-20-2006, 03:20 PM
That makes no sense. If the engine was cold it would be better to keep the revs down, not force them to go higher.

I guess they trust the engines not to have problems revving when cold.

swng
02-20-2006, 06:12 PM
A possible reason for that is the car wants to heat up the catalytic converter as soon as possible so that the emissions will be cleaner. The catalytic converter cannot function with good efficiency when cold. Higher revolutions at the engine achieved by restricting upshifts to no higher than the 3rd gear can produce more hot exhausts to warm the converter up.

why?
02-21-2006, 10:44 AM
A possible reason for that is the car wants to heat up the catalytic converter as soon as possible so that the emissions will be cleaner. The catalytic converter cannot function with good efficiency when cold. Higher revolutions at the engine achieved by restricting upshifts to no higher than the 3rd gear can produce more hot exhausts to warm the converter up.

You are prolly right. That does make sense that it is emissions related.

TRD_Yaris
07-22-2006, 03:06 AM
A possible reason for that is the car wants to heat up the catalytic converter as soon as possible so that the emissions will be cleaner. The catalytic converter cannot function with good efficiency when cold. Higher revolutions at the engine achieved by restricting upshifts to no higher than the 3rd gear can produce more hot exhausts to warm the converter up.

and the Genius of the Day award goes to.....

07WYarisRS
07-24-2006, 09:54 AM
Higher RPM's + lower gearing = less load on the engine.

running a cold engine under load is hard on it, the less load the better providing the rpm are kept the a common sence level...

paultyler_82
07-29-2006, 08:03 PM
Higher RPM's + lower gearing = less load on the engine.

running a cold engine under load is hard on it, the less load the better providing the rpm are kept the a common sence level...

I'm glad someone said it, thank you 07WYarisRS, please people, don't be trying to break the land speed record in third gear with a cold engine.

Katana
08-06-2006, 05:40 AM
Anyway, I am sure that my Yaris goes better if you rev it up to 5300rpm.Always with manual transmission of course!!!