 Really don't know what it could be. My timing is a 15 top, four top dead center like the factory service manual states. I don't know what it could be. Yeah, well, just before we mentioned that, unfortunately, we don't have a crystal ball to diagnose things either, but we're here to help you if we can. So I'm going to back you up. Tell us what kind of vehicle you're working on. It's a 1993 Nissan 300ZX twin turbo.