[jackmech]

And finally, for the 100th different solution. Check your vacuum advance canister. Take off the dist. cap, take the advance hose off the throttle body, suck on the hose and make sure the plates move, then stick your tounge over the hole and watch to see if the plates slowly (or quickly) move back. A good canister should hold their advanced position all day. I've seen plenty of bad canisters.