[Freerider777]

2019 CX3 70k miles. I just noticed the other day a low frequency noise of some kind in the lower area of the engine. It's not very loud at all. In fact you wouldn't notice it at all unless you drove it everyday like me. It's only noticeable if your're inside the car and it can only be detected at an idle. No perfomance has been lost. Has anyone else noticed this? It could also be coming from the transaxle but can't tell for sure.

 

[Slick280z]

Check water pump first, if its in that area remove water pump belt and test with just serpentine belt. If noise goes away its probably the pump. Mine made a noise for a long while, about 30k miles and I thought it was just the engine noise people always talk about. But indeed it was the pump. It uses a stretch belt so replace it if possible.

 

[Freerider777]

I'm noticing that I don't hear it in the morning when the engine is stone cold. I recently changed the oil and used the recommended Castrol. All the previous oil changes were at the dealer, and they have told me that they use Valvoline. My next oil change I'm going to use Valvoline and see if the noise may go away.