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Q: Knocking sound when driving. Disasters when braking or accelerating.

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When I drive I hear a knocking sound that gets more frequent the faster I go. The knocking only appears when I cruise, if I'm braking or accelerating the sound disappears. Been under the car today and I've noticed my heat shield is slightly loose and close to my exhaust. Could it be hitting the exausht as I drive??

My car has 60000 miles.
My car has a manual transmission.

A: If the knocking only appears when you are a...

If the knocking only appears when you are at cruise and becomes more frequent as you go faster, then you may have an axle inner joint or a transmission mount or engine mount issue. This may be why the noise goes away when decelerating or braking. See if the noise comes and goes if you cruise and let off gas and get back into the gas to see if noise comes and goes. If it does, then try and see with a passenger’s help to see if you can isolate where the noise is coming from. For example, is it the left or right side? This will help to explain the noise to the mechanic when they come and pinpoint the cause of the noise.

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