Chevrolet Repair: spark advance, chevy k1500, fuse block

Question
i have a 1993 chevy k1500 5.7 4x4 i am having trouble with spark knock i have to run my timing retarded to keep it from knocking. it runs an idles ok but if i get into the throttle it looses power... the distributor is fixed{no adjustment}for the spark advance. would a bad egr valve be the problem?

Answer
Ok. Start from scratch(as long as you haven't pulled the distributor)Check to make sure your wires are hooked up correctly. Then, up near the fuse block on the firewall there should be a brown wire with with a simple in-line connector, unplug it. Then start the motor, bone stock you should set the timing at 0, no more no less. Make sure it is up to temp first though. Once your at 0 shut off the motor and put the browm wire back together. The timing should automatically advance on it's own when you get on the throttle. If the truck is still not running right after this get back to me with a follow up and I will help you some more.