Hi, I have an 88 civic and knocking is coming from under the hood. I thought maybe the engine was just getting old so I switched to premium for a while but it has just gotten worse. It's knocking a lot but I don't think it's the engine as it knocks at various times not in accordance with how I'm running the engine. I guess I will take it in but can anyone tell me what I'm probably facing? It sounds like it's coming from the passenger side front wheel. thanks a lot