I purchased a 1987 Club Car DS and noticed after the fact that it has this knocking/pinging sound when throttling or at the very end of letting off of the throttle. I have noticed this issue more since the cart ahs been ridden more frequently than before. I tried to do an oil change when I first got it, but the drain bolt was stuck, so I had to use that sucker tool to get out what I could and replace it. The oil did not look healthy...at all. I am also noticing a light amount of smoke when I first get it going. Below is a link to the video of the cart being revved. The noise is at the very beginning of the rev and some at the tail end. Any ideas of what this is would be greatly appreciated and any ideas to the cost of fixing as well. OR, if it would be best to move it on.