You may have a vacuum hose leak. Check for cracked or broken small diameter hoses coming from the intake manifold.
get the person out pf your trunk...lol
check CV joints
fuel pump will only run when ign on for few seconds to pressurise system and will only pump while cranking or eng running,this is normal. most likely cause is ign module or coil which are both in distributor.
Check your cooling fan motor. If it is no good when it goes on it will make a pulsating sound.
Low coolant causing air bubbles in the heater core.....
yes. All objects accelarate torwards the earth at 9.8 m/s2 So you could test a golf ball and drop it with a bowling ball or something similar. It takes longer for the larger object to accelarate, while the smaller object accelarates faster but doesnt accelarate much after that so the technically they are balanced in the air. But you cant test a peice of paper and a basevball because the peice of paper would have a larger surface area and more friction would slow it down longer. But yes that is a valid science project. G luck
main shaft bearing
it might be a bent piton rod if you or water or somthing into the engine
Is it accompanied by a shuddering or vibration? You could likely have bad brake rotors.
Sound waves are vibrations that travel through a medium, such as air, and can be perceived by our ears as sound. These vibrations cause molecules in the medium to compress and rarefy, creating fluctuations in pressure that our brains interpret as sound waves. The frequency of these vibrations determines the pitch of the sound, while the amplitude affects its volume.
A reflection is the bouncing back of sound waves off a surface, while an echo is the repetition of sound caused by the reflection off a distant surface. So, a reflection can contribute to creating an echo by bouncing sound waves off a surface, leading to the perception of a repeated sound.
if your car has air con on it while the engine is running it will be the aircon pump switching on and off hope this helps you out nate