So.. I finally went to get some O2 sensors. I got two bosch's. Installed them, and nothing has changed. My truck is still throwing codes P0172 (Fuel System Rich Bank 1) and P0175 (Fuel System Rich Bank 2). So bad oxygen sensors are not the problem anymore. I ran a vacuum leak tester over all of my vacuum hoses (I think) but it picked up nothing. The only thing it beeped on or around was my intake manifold, but if the gasket around it was leaking, wouldn't that mean i would be sucking in unmonitored air, and causing my truck to run lean, not rich? Oh and one more thing, could it be because i have an exhaust leak around the flange that connects the header to the exhaust pipe? It's just on one side though.. Anybody who can help, it would be appreciated. I have to get it running right before i start deeply modifying it. Thanks.