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What is the cause of knocking sounds underneath the car when the engine is idle?


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2015-07-17 17:45:34
2015-07-17 17:45:34
could possable be loose torque converter boltscould be a motor mount

Check the oil level. Sometimes being low on oil causes a knocking sound.

i would have to say i bet 9 times out of ten its the harmonic balancer dos the noise get louder when put in reverse.....? if so that's definitley what it is.......new there about 100 bucks but you can most likely find one at the junk yard for cheap 20 bucks..... i would advise to rent a harmonic balancer pulley from the nearest auto zone you will need

im not too sure it has anything to do with the oil, if it was low enough to make the engine make noise, the oil level sensor light would have came on the dash . if it where a motor mount, you would know. every turn you make you would feel the engine shifting, and it would be a lot louder than a knocking sound. although i have the same knocking issue with my 03 Gt, and all i did was tighten the valves. if you are mechanically inclined, you can do this yourself in less than an hour. if not don't try! take it in to any shop and pay 1 hour labour.

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Cause low pressure oil pump

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When the fuel in an engine cylinder ignites prematurely or unevenly to cause power fluctuations and a "knocking" sound. usually occurs when an engine is very how or improperly timed.

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Engine knocking can be caused by numerous things. Having the incorrect spark plugs, carbon deposits on the cylinder walls, and being low on engine oil may all cause a knocking sound.

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can you elaborate? engine noise? stationary/moving? ticking, tapping or a definite knocking?

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Yes, fouled spark plugs can cause engine shaking, and loss or power. I'm not sure about knocking but I'd guess that too.


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