Surging and hesitation with Air con on

[stevieg]

Here's a new one on me, hopefully someone has some insight on it.
Kia Rio 1.5 Diesel, UK model, runs smooth as a die normally, i.e. smooth acceleration and deceleration, smooth constant speed and so on. Hit the AC button to cool the cabin down and we get surging and hesitation from the engine, especially when decelerating and accelerating. The AC is working fine, i.e. nice cold blast from the vents but it's a pig to drive it. Switch off the AC and all returns to normal.

It's like the ECU has forgotten how to handle the extra load from the AC compressor and just hunts around the fuel map hoping to strike lucky.

Any thoughts. I'm going to ask the dealer to pull out any DTC's but just wanted to know if anyone else has had this kind of thing.

One thing I have found which maybe related is the AC pressure sensor could be reading high or low, but not sure how this error really manifests itself.

[Streetwalker]

Just tried mine on a short sainsburys hop, at low speeds on the max-aircon setting the performance is sluggish, like the compressor is being overdriven & sapping power so to speak. On the normal setting there is no real difference with a/c on.

[stevieg]

Typical, problem didn't happen for me or the technician today, however I think that since the day is a little cooler, than of late, we may not get the problem apart from on really hot days. So, anybody know what that might mean. Is it a sun sensor problem? Cheers.

[Streetwalker]

Maybe a temp sensor in the car then, when I went out on wednesday it was 30 c outside, the temp in the car when I got in it was somewhat in excess of this.

[Obione1975]

This is exactly why I chose to stay away from A/c this time. I had it in my first rio and when i turned it on, I lost half my horse power is what it felt like. No good. Ill just roll the windows down

[drwho]

Hello Stevieg
Please Would You Look At
At My Information On The CARRENS Forum PAGE
Please Look For (car Jerking )
(id Drwho)
Same Probem As You
But (I OWN A CARENS RONDO MODEL)
My Problem Is Solved With Aircon On
Hope To Hear From You
Drwho (steve)

[stevieg]

Hi drwho, you're only 30 minutes from my place, I suspect you are visiting Gravells in Swansea.

Anyway having read your thread I see you're awaiting a new PCM cal to be flashed on which should be an easy thing once they get the software. Not sure there's any such PCM update due for the Rio and after 85000 miles without any trouble my suspicions lie elsewhere than the code and hopefully something a little simpler.

Would appear that the air con issues I'm having are only on stinking hot sunny days.

By the way you won't freeze in the winter with air con on, but it does take a couple of degrees off the heater setting. There is the added benefit of keeping the air dry so you keep the windows clear though.