Mazda 3 Very high idle on very cold mornings..normal?

[tgrudzin]

Mazda 3 '07 120K. Owner since 10/2014. I noticed it idles really fast on cold mornings, and the colder the faster. Yesterday, outside temp at +1 Fahrenheit, it started and went immediately to 2500 RPM and stayed there for some 30 seconds then started to slow. It's hard to backup (5spd) down a long driveway at that speed. When the temperature was say in the 20's, it would fast idle around 2000 then make it's way towards normal. Is this normal? Otherwise the car is fine, no codes and just past Illinois emissions test with no issues.

 

[njaremka]

normal

 

[concept]

Yes, my 2014 Mazda does the same, although my garage temp never exceeds 55F or so. The idea is to circulate the oil as quickly as possible. I remember reading a book about engine rebuilding in which the author recommended keeping the newly rebuilt engine speed (upon initial startup) at 2000-2500 rpm.
Of course, you should not drive away when the engine speed is at that rpm for 2 reasons:

1. It's hard on your transmission or clutch.
2. The oil needs some time to fully circulate and pump up to pressure when it is cold.

 

[GAXIBM]

It is about pollution - heating up the cat quickly with rich high rpm.

 

[Bruns]

It's mandated by law.
Any new motor vehicle must warm up its catalytic converter within a certain time frame. Therefore the car starts and runs a higher rpm to warm up the exhaust.

GAXIBM got it right.


Sent from my iPhone using Tapatalk

 

[Mazda32015]

Absolutely normal.