My car suddenly stopped running today while driving. When I turn the key the car cranks strong and i hear a repeating putting sound when cranking like the car is trying to start. I poured about a 1/4 cup of gas in the carb and the car ran for about 5 seconds but very roughly. Also, from time to time the engine would lose power and backfire and I would have to either turn off and restart the car or rev the engine really high for a few seconds for this to go away. I'm wondering is this a timing problem, or do I need a new fuel pump?

 

It sounds like the same problem I'm having in an '08 STS. Could be, if the older models have these, the ignition coils, sparks plugs (misfire), camshaft and crankshaft sensors (timing). If you're still driving on a misfire I feel it's safe to say the ECM could need replacement from driving under these conditions which is why it won't start, this could also drain your battery.