The knocking sound could be the doors of the vents closing when you turn it off,they are controlled by vacume.Or it could be the plastic making the sound due to change in temperature. If it is a early to mid 90's Chevy it is most likely the actuator solenoid that controls the recirc or fresh air. If it is it will knock for about a minute and 30 seconds when you start the vehicle and about the same wheen you turn it off.
Suspension is the most likely cause of your knock when turning. The part responsible is probably your tie rod, which is what allows you to turn the steering knuckle. They are inexpensive and easily replaced. You can avoid an alignment fee by being careful with your measurements during replacement.
most likely a bearing has gone out
I get it this way... knock on heaven's door, and listen its reply.
NO it will not. If you have a knocking sound then you have trouble inside of the engine.
Worn ball joints?
Singing water pipes can be caused by air that is trapped in the pipes. The air can cause a whistling or singing sound, or it can cause the pipes to knock or rattle.
The cause of the squealing sound is because you are turning the steering wheel completely to the right or left
If it is a front wheel drive sometimes a bad cv joint can cause a popping sound when you are turning.
Low coolant causing air bubbles in the heater core.....
if its a front wheel drive vehicle then it could be the axels
I read that bad motor mounts can cause this knocking sound