Used 2004 Ford Explorer XLT V8 4WD for Sale near Springfield, IL

I was driving down the road and my engine started to knock. My fluids are good. Im not blowing smoke burning oil and theres no check engine lights. I put a code reader to it and it only says bad ignition coil. Idk what else to do or consider being wrong with this car to cause a knock

I love my car except it guzzles gas way too quickly Not too many miles to the gallon on my half. I love the way it sits up high and is safe. The only thing is that it easily flips. I love going mudding in it. The tires have good tread. For a big car that is not a sport, it has pretty good pick up and the breaks work amazingly. Unfortunately I had to get the wires cut and rewired because the alarm kept going off and wouldn't shut up