ECM problems?

Ok, I am curently driving my 84 caprice 305 without the ecm connected to the distributor.
Reason being is when my engine warms up, when i shift into second or third the vacum advance backs off to much and the car hesitats like crazy.
and when im going up a hill or pushing hard on the gas the vacum advances to much and i hear along of clanking noise in the lower engine.

but with it disconnected my car runs just fine, but lacks the power becouse theres no advance.
Any ideas on how to fix this?

also, my timing mark is way off, If i set it where its saposed to be the idle is extremely low and dies when i put it in gear, if i get it to stay runing i have no power what so ever. didint have this problem till i replaced valve covers and Egr valve

Thanks
Mike.

check for a vacum leak at the egr valve! check all the vacum lines that you disturbed while replacing the valve covers as you may have put them back in the wrong place or you may have broke one! Also if the engine noise you mentioned is more than just pinging :usaualy from incorectt timing your bad fuel then you may want to consider rebuilding your engine or replacing it before it becomes a boat anchor.