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Q: Engine light was on it started with a slight knock on a cold morning. It didn't stop and it got worse.

asked by on

can this problem be fixed without a engine swap

My car has 156000 miles.
My car has an automatic transmission.

Hi there. Depending on the sound of the knocking noise and where the noise is coming from on the engine will determine if the engine needs replaced or not. If the noise is near the top of the engine, then the tapping or slight knocking noise is the lifters tapping as they are collapsed with no oil in them. This is done from the lifters sticking or the engine oil pressure dropping. First check the engine oil and see if there is oil present on the dipstick. If there is oil in the engine, then I recommend replacing the engine oil if the oil has not been changed in a long time as the filter could be plugged up. Then if the knocking sound is still present, then put a oil pressure gauge on the engine’s oil gallery and check for oil pressure as the engine is running. If the oil pressure is low at idle and rises as the engine is throttled, then the engine rod and crankshaft bearings need replaced. If the oil pressure is lower than 8 psi and does not increase and the oil filter was replaced, then the oil pump pick up tube is either clogged or the oil pump has a broken gear. If the engine knock is in the lower section of the engine and is not near the top, then you have either a rod bearing that needs replaced or a piston skirt is slapping the sidewall of a cylinder due to too much wear. I recommend seeking out a professional, such as one from Your Mechanic, to help you diagnose your engine knocking sound.

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