Q: Check engine light on, engine knocking, loss of power, and coolant leaking.

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Hi,

My car recently had its engine replaced because oil had leaked out. Everything had been running smoothly for about three weeks now.

Today, after parking my car, the check engine light came on. I stopped the car. The oil was full, but the coolant was empty. Not having coolant, I drove the car for less than a mile when I remembered a friend of mine left spare coolant in my car. I put this in but noticed that the temperature gauge had already gone to the halfway point.

I drove the car 4 miles to a mandatory meeting and parked. Afterwards, I drove uphill 3 miles. I started to hear a quiet knocking noise and loss of power. I decided that adding the coolant wasn't enough so I drove the car straight home.

Later, I noticed the coolant leaking from under the car but the coolant reservoir was still full.

My main concern is, did I ruin the engine again?? What other issues could explain this?

My car has 90000 miles.
My car has an automatic transmission.

Hi there. Grab a flashlight and look under the vehicle for where the coolant leak is coming from. Either there is a gasket, hose, or freeze plug that is leaking causing the coolant to leak or the engine has cracked. The knocking noise is from the engine getting too hot and causing a detonation sound. If there is a crack in the block, then it could be from a piston rod that broke off. The loss of power is when the engine had not enough coolant to operate properly and caused the engine to overheat and not burn the fuel properly. If you need further assistance with your engine having a coolant leak, then seek out a professional, such as one from Your Mechanic, to help you.

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