Kia Rio Aircon


Expert Member
May 28, 2008
Hi all,

I am wondering if anyone else has this problem or if it is just me.

When I use the aircon on my Rio 1.4 it saps so much power that if I need to go up a hill I need to turn the aircon off.

I do understand the aircon will use engine power but so much?

I was in 3rd gear the other day de-accelerating at about 40km/h with the aircon on and it was almost as if the car was going to stall at that speed. There was a lot of engine braking. As soon as I switched the aircon off it was as if a load had been lifted off the engine and the car felt more free.

Not sure if I am explaining it correctly but just wanted to see if anyone else has had such a problem on their Rio or if anyone can shed some light? Car is almost 2 months old.

In my mind, an aircon should be almost unnoticeable - especially the newer electric ones.



Executive Member
May 23, 2006
I have the 1.6 Cerato which I assume is quite a bit heavier and I have never noticed any aircon power drain. I have tested for it as well as I remember on my Bantam, pushing the aircon off was like hitting the NOS button.


Expert Member
Jan 6, 2006
On a 1.4 you're really going to notice the power drain when you have the aircon running.

Not sure which year model Rio you have, but the newer ones are quite high revving motors so if you aren't up into decent revs the engine will have very little power and with the aircon sapping probably around 5-10kw of your power you're going to notice.

I notice it even on my Golf 1.4TSI which has decent power and torque from low down in the revs, max torque is available from 1500-4000rpm, it far less notable than it was on my previous car which was a 1.6 Polo but I still notice it.


Honorary Master
Jan 30, 2004
Not just a 1.4 motor, my cerato 1.6 also feel like a truck with aircon on. Besides with the petrol prices i prefer not to use the air con unless i am in traffic. It zaps power along with huge amount of fuel.


Executive Member
Jun 8, 2008
An aircon will generally suck the zest out of a 1.4 motor.

I drove a 1.4 with zircon. I used to call the air con button the "Air brake" button as the car lost so much power it was scary.

Even in my 1.6 Polo I notice it - although not anywhere near as bad a 1.4.

In the 2.0 motor you just don't feel it at all.
I drove a Golf 5 2.0 for a few days and turning the air con on or off was only noticeable by the cold air coming out the vents.


Senior Member
Jan 6, 2012
I also have a 1.4 Rio, and while the car does feel a bit more sluggish with the aircon on, I can't say I've experienced this to the extent you are describing

Type RSA

Expert Member
Aug 31, 2011
My fiance has aircon on her 1.4 Fiesta and the same thing happens. It is normal on "lower" powered cars.


Honorary Master
Apr 30, 2009
I've driven my Dad's Kia Rio Tec 1.4 and I can say it's one of the best aircon's out there. The Kia Rio (Tec) has an electrical aircon which doesn't use the engine power.

I'm sure there will be a slight power drain, but not to the extent you described it.

I've personally driven the car from JHB to Margate with the aircon on and didn't notice the aircon sapping power from the engine.

P.S. Not sure if the Kia Rio 1.4 is different from the Kia Rio 1.4 Tec when it comes to the aircon.


Expert Member
Jun 4, 2006
Lower capacity engines have less torque and power to play with.
An average aircon compressor uses up to 5kW peak while compressing the aircon gas.

Some thumb sucking estimates:
5kW at 3500RPM is only 10 Nm but 5kW at 2500RPM is 14Nm (assuming a variable flow AC compressor is used).
That may not seem like much but the Rio 1.4 only puts out 135Nm at 4200 RPM and the torque curve drops off rapidly below 3000 RPM.
The 1.4 will probably put out around 85Nm at 2500 RPM.
This means that the aircon compressor is using up about 16% of available torque at 2500 RPM.

Assuming the same air con system is used:
On a larger capacity engine (Kia Cerato 2.0 for example) the torque at 2500 RPM would be around 122Nm which means that 14Nm would only consume around 11% of available torque which would be less noticeable than on the 1.4.