How does air conditioning affect your engine?

With summer on the horizon, I’ve been starting to think about investing in a vehicle and hitting the open roads.  Scanning the online car listings, you soon get an idea of what’s important, and I reckon having a reliable, working air conditioning unit is key to a comfortable ride, no matter what season you’re in.


Having always been curious about the way air conditioning can affect a car’s performance, we’ve done a little deep dive into the subject.

Basically, every time you decide you need to cool-down or warm-up, your air conditioning system starts to draw power from the engine.  All good, but bear in mind it’s also sending power throughout the rest of the car as well, including all those little pumps, valves, the power steering, and so on.  So, yes, there can end up being a little bit of an internal power struggle, if you will.

You might notice your RPMs increase while you’re at a standstill with the air conditioning on blast.  It’s just working that little bit harder to keep everything going.  That said, it’s pretty hard to determine exactly how much power each component is using, it comes down to a whole bunch of variables, not least your car’s make, model and year, as well as its general condition.

It’s worth noting that air conditioning draws more power from smaller, city-bound cars than their larger, full-engine contemporaries with V8 or V12 engines.

However, if you’re a speedfreak, you’re going to notice these fluctuations in engine performance a lot more, not matter what car you’re driving, or whether the air conditioning is switched on.  Minor accelerations can result in unsuspected shifts that are caused by the dynamics of your engine’s power draw, including whether you’ve got the air conditioning on blast.  The status of the air condition can definitely have a bearing on the intensity here.  

More conservative drivers are less likely to really notice these differences, and hey, each to their own, we say!

So, how can we minimise the impact of air conditioning engine performance?  Here’s a few ideas to chew on.

  • Use air conditioning sparingly!  If there’s a natural breeze you can take advantage of, wind down the window and let it blow through the car for a couple minutes to refresh and cool you and your passengers down.
  • Avoid drastic temperature changes. Adjust your AC temperature according to the outside temperature, try not to create a drastic temperature shift between the inside and outside conditions.
  • Give it a couple minutes after you start. Given your air conditioning is power-hungry, don’t have your AC switched on when you turn on the ignition.

So, yes, while it is quite the unbeatable feeling to step into an air conditioned car, its worth bearing in mind that this experience enhancing feature does take a toll on engine performance. Though, with a few conscious habits, you can avoid feeling the battery burn of long rides in harsher climates, or freezing your way through traffic in the morning.

Just stay mindful of the extra pressure that’s being put on the engine and you’ll be fine.  If you are thinking it’d be worthwhile getting your air conditioning checked out by a professional, the team at My Auto Shop can make life a breeze with a local mechanic that meets your budget. 

Just head to the My Auto Shop service area and we’ll get you started.