timing and advance

:banghead: Is anybody familiar with electronic spark timing (est). I have a real pain in the ass problem. First off I have 93 chevy full size blazer 5.7 4x4. The problem is that the timing does not advance with rpm. I disconnected wire to set timing to 6 degrees base timing then reconnected wire and erased codes. I started engine and timing is now at 20 degrees. When I give it throttle the timing stays at 20 degrees no matter the rpm. Shouldn't it advance with rpm. The power the engine puts out is sluggish. The engine is not knocking to cause it to retard timing. I would really appreciate any response. :eek7:

see what happens to timing if you put it in drive, hold the brake, and give it gas. Are you using a timing light or scantool?

I used a timing light. I tried putting the truck in drive holding the brake and pushing on the gas. The timing retarded about 6 to 8 degrees then went back to 20 degrees.