I let my car run too long without oil and it started knocking when i'm on the gas...i put 3 qts in and let it run abit...hit the gas and when i'm on the gas hard it knocks still...what is causing this
Could be just the gas your using, it's called detonation, or you hear valve ticking. Have a mechanic check it out for you and see if it's worth fixing the oil leak based on if they find internal engine damage.
Oil is your engines life blood, without it damage starts to happen, if it sounds like a deep knock chances are that you have damaged rod and or main bearings, if it is in the top end it could be lifter clack do to lack of oil or you could have destroyed some cam lobes. Do what Tom suggested, have to checked out professionally. 1973 last of some of the good ones.
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