@d3br34k5
Fair enough, the point you stated is correct, I admit it !
On the other, being a mechanical engineer and several times being involved in a race environment (preparing and racing the car) three things are coming up with what you are saying.
First, about normal cars (production cars i mean) it could be a possibility to scroll down the window and quickly check some wired sound, but if this work on a normal road or even on the nurb, on other tracks which other cars/public noise it's just impossible, you can only hear exhausts.
Second, as a race driver, you are wearing an helmet with radio hearplugs, and even if you can usually detect the sound of an air bubble circulating inside the oil pump, you wont hear anything, trust me.
Third, by having experienced it, when a problem comes from your tire, if during normal drive (e.g. drive to office) the sound is more important than the feedback on the steering wheel, during race condition, due to car setups and customisation, a small problem at the wheel, you will straight feel it on your hands.
Also it would be more accurate from PD to actually make the controller vibrate(dualshock)/oscillate(stearing wheel) than just display a sound and hope the player will hear it.
But not to put you down, i admit that improved game sound (surround also) would definetly had a huge amount of immersion at the game !!!