Can someone help me I have a 1984 Buick regal V6 3.8 that I've been trying to start for the pass couple of weeks and just can't get it to start. The engine turns but it wont start. I replaced the spark plugs, spark plug wire, cap and rotor ignition control module, I have check for spark. The starter is good. Since I could not get it to start and I thought it was the engine starting to freeze I changed the engine with another that I had. now I still can't get it to start . Any suggestion of what to check