I appreciate your answer but I’m sorry to say I didn’t understand it. A guy my mom know’s change the rod barrings in it the other day but it still is making that knocking noise. What I was saying was when she turns it on, it doesn’t make a knocking noise. It only makes the noise when she gives it gas. She try driving it the other day but when she got about 2 blocks down the rode the van died.
To answer a couple of your questions; when she just turns it on and just sits in park and rev up the engine, it makes the knocking noise. It sounds more like thunking noise.