the lights on the dash, brake ABS and Track come on and go off , I have other volvos and have had the same problem. Whats it take to fix this problem?

the timming belt came off, bad pully, and I have a new belt installed just to see if the car would run, it did and only smoked when you took off. I pulled the head and had a shop do the head, 2 valves bent, they put nes valves in I reinstalled the head and now it smokes more than it did. I feel it i...