Why does this happen?

Today, i decided to start up the stang, its been a week since I last started it, This week I replaced the heater core during the week. Today this morning when I tried to start it up it didn't want to, be battery wasn't charged enough, so we jumped it. After, it started up fine. I drove it around to do some errands, and during my last errand I noticed that it wasn't starting up the same. I would turn the key, the alternator would turn and turn and turn but it wouldn't start, then after holding it down for a while (3 seconds, like 1 one thousand, 2 one thousand, 3 one thousand) it started.
Then I came home, and turned it off, and 10 minutes later i tried to start it up again to move it into the garage, well this time it really annoyed me. She didn't want to start at all, I pumped the gas pedal, turned and held but she didn't ant to start. After a few in a row she finnaly starts and then stops, I try it one more time and this time she starts. At this point i'm kinda angry, what did I do? last week it was perfectly fine why is it acting up now.
Any ideas?

Edit: Btw: There is gas in the car, but if you open the door it smells like gas, but there are no leaks of gas under the car
 
Hmm... sounds like it could either be 2 problems or just 1 problem. Sounds like no matter what, you definately have a drain on your battery when the car is off. If that is the case then you will have a dead battery every time the car sits for a few days or even over night.

The other possible issue could be the starter motor itself. You might want to pull the starter motor and check it to see if the teeth on the gear are chewed up. If they are then I sugest that you replace the starter.

Do you have a manual or an auto ?
 
The alternator could just be bad. Maybe its just not charging the battery. I had a problem similar to this except I had wires hooked up wrong when I put my new engine in. Take the alternator to a place that can test it.
 
Well,I know that the flywheel has a bad spot on it,both the mechanic I took it to and a different problemI described on the boards once told me that. It does sound like a metallic grinding sound every once in a while, but everyone says to just put the key in the off position and try starting ti again until u get the point where it doesn't start at all or when I pull the engine out over the summer.

As for the battery, this is the second battery within the month that I've had this car, the original one i said maybe it just doesn't work cause we couldn't get it to jump, then I replaced it with a less powerful one that I use to charge my model airplanes with and then it worked fine.

It is an automatic, everything is original on the car,original engine,tranny,gauges even seatbelts.
The previous owner did an absolutely miserable job on the wiring he added his own set of stuff and didn't add em correctly. I'm planning on getting a g3 alternator froma junkyard soon and a new wiring harness.
Any idea of what the drain could be?
 
Sounds like you definately have an electrical problem. Pull your alternator regulator and alternator and take them to a shop to get them tested just incase but I think if it wasn't making juice the car wouldn't run long after you jumped it.

Start by pulling all the fuses on the fuse block. Then charge the battery. Check the voltage on the battery after its charged. Put the fuses back in 1 at a time and check the draw on the battery every time you put a fuse back in. That should get you started on trying to find the problem circuit.
 
hmm,
when we jumped it this morning, it started up in an instant, ( I think with the previous battery the jumper's weren't connected properly, it was at night and practically no visibility)

I'm sending the car to the painter on monday, and hopefully we'll be able to get him to completely strip the interior as well, if we can that i'm definately going to buy a new wiring harness, and gonna replace the fuse box anyway.

In terms of the alternor, where do you guys suggest I take it?

Cause like mentioned above, i am looking to purchasing an old tarus 3g alternor (130 amp i believe). The reason why i'm getting such a powerful amp is because i'm planning on putting a powerful stereo system in it.

My friend who owns a part shop says he knows this one electrical guy that knows mustangs inside and out, so i'll talk to him too.
 
K, I checked the voltage this afternoon and it was 12.9 v, before I started it. After, it started up just fine, quite quickly as a matter of fact, and then it was putting out 14.3 volts.
The grounds for the alternator and battery both go to the engine block itself, I took them off, sanded the rust and dirt off, and put them back. and the once again teh car started up without a hitch once again.
I also checked the voltage on the other battery and it was 9.2 volts, I might be able to save it.
Wierd...