So the car is turning on but the timing chain is off, but is making a quick knocking sound.
My car has 190000 miles.
My car has an automatic transmission.
Hello. If you know that the timing chain is off then the engine should not run. If the timing is correct but the chain is loose due to other issues then that may be the knocking noise that you are hearing. Most of the time if the timing chain is off then there will be no compression in the engine and it can also cause some engine damage. If the chain is simply loose due to a failure in the timing chain or a tensioner issue then that may be the knocking noise you are hearing. I usually check the compression first and also remove the front cover to inspect it to see what it needs. If you need to have this engine knock checked, consider YourMechanic, as a certified mechanic can come to you to [diagnose why the engine is making this noise] https://www.yourmechanic.com/services/noise-from-engine-or-exhaust-inspection
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