This dumb site wouldn't allow me to post in the general tech section so here's my question. I have a stock d15b7 and I just started having problems with it. It won't start at all without a jump, so I think I need a new battery for one. But then, when I get it started and rev it up, it sounds frickin WEAK as hell and my engine was KNOCKING before when I started it but for some reason that stopped. I recently put some 10W-30 pennzoil in it I don't know if that's the right oil but that's what a mechanic told me to use but I'm not sure. So, what kind of oil should I be using on a stock d15b7 (my bad I have a cold air intake, headers, and exhaust) with 60k miles? And could that be my problem?