1988 Chevy Truck ignition timing?

I installed a new 5.7L 350 engine in my truck. I didn't have a timing light handy when I went to set the timing. I used the same distributor from my old engine and adjusted it by the idle sound. It sounds good and everything, but the idle picks up and bogs down... I even put a timing light on it and adjusted it the way it was supposed to be. Wow it idles great now, but now when I drive and push on the gas I loose all power and my check engine light comes on. Could this be that I need a new distributor? I ended up adjusting the timing back by sound because I could not drive with it set with a light.