Can the heat cause my car to not run as well as usual?

Question

I know that cars can overheat, but my car is just not running as well as it usually does - its a little louder. I've checked my fluids and they're all fine.....so could this be related to the heat or my needing an oil change?

Answer 1

If your car has a mechanical fan on the engine instead of electric fans it will make more noise when it is hot outside. This is because the mechanical fan clutch tightens allowing the fan to pull more air across the radiator. Cars do run better when its cold because the air is more  dense allowing more oxygen to get into the engine. Should still change the oil.  

Answer 2

Yes and yes!

There could also be a failing sensor. I am having to replace a tempsensor on my Mazda because it tells the engine what temp. the engine is operating at. This has an impact on timing, fuel ratio as well as turning on the radiator fan.

So you may want to check the engine temp sensor that works with the computer, as well as the one (if your car has one) that lets the ECM know what the inlet air temp. is.