What's Wrong With My Car?

Today was the day I was going to replace my car starter. I have not touched it for a couple of weeks while I waited to get paid from an assignment. But I decided to try the ignition one more time. I discovered its behavior has changed, so that now the starter is engaging.

Previously the electricity all came on, but there was no sound, not even the clicking sound coming from the starter solenoid.

Today the starter makes this rythm: "DAdadadaDAdadadaDAdadadaDAdadada." The engine makes its normal "whoomph" sound for the tiniest fraction of a second and then dies, even if I push down the accelerator. The dashboard "FUEL CUTOUT" indicator lights up.

So now I no longer know what to replace. I may have to take it to a mechanic, but that is a serious last resort. Any advice?

Car Is Running Again

The car runs fine now for some reason. My best guess is that the fuel turned to jelly when I left it for a few weeks, and constantly gunning the accelerator during ignition might have flooded the engine. I got a jump and it acted the same, but as soon as I tried it without the gas pedal it started.