FrizzleFry

I have an 85 silverado, 350, 4 barrel carb, 2 wheel drive, auto transmission. My check engine light is on, the codes are saying its the coolant sensor, map sensor, and the o2 sensor. I replaced all 3 things but its still showing the same codes, new code popped up afterwards and it had to do with the ecm. Would replacing the ecm fix those problems, or would I have track down each wire and see if the wire is the problem. I read in a chilton book that if there are too many volts to one of the units it would cause the check engine light to come on as well. I've been working on this truck for some time now, got it all rebuilt, and would love to smog it and have it on the road ASAP. Just was looking for a quick helpful answer instead of having to pay someone to check the electrical and possibly run new electrical or whatever