Pontiac: No start, armature windings, pontiac grand prix

Question
Had the starter replaced this weekend, still doing it.  The shop thought that the anit-theft device was shorting out causing this problem, so they disabled it.  The very next day (after sitting all night) it wouldn't start again.  Any other suggestions?

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Followup To
Question -
We have a 1996 Pontiac Grand Prix.  It has been doing something bizarre.  Every now and then, it won't start.  It's just like the battery is dead, but the radio works, the power antenna works, the dome light works, etc. but the engine makes absolutely no noise.  If you wait a few minutes and try to start it again, it'll start right up.  It's not like it's trying to turn over or anything, it's like it's dead.  It doesn't seem to have any pattern to it either.  It may do it 3 or 4 times in a row, and then not do it for a few days, then it starts doing it again.  We thought maybe something was heating up, but then it did it in the garage one morning after sitting all night.  We took it to the local auto parts store and had them put there load tester on it and they said the battery is good (11 volts), the alternator is good and the starter started within the allowed time (hence I guess that means the starter is good).  I took it to my repair shop, but of course, it wouldn't do it there so they found nothing.  We changed out the battery cables thinking maybe there was a problem there, but no luck.  We checked all the fuses and relays that we could find, but they all appear to be good.  We're at a loss.  Can you suggest anything else we may have overlooked?  

Answer -
It is probably the starter. Sometimes they get a dead spot in the armature windings. It will start every time as long as it is not on the dead spot. The test they did on your starter would never show this problem.

Answer
You could have a problem with the ignition switch. We have alot of problems with them. You need to find out if you are getting power down to the starter on the purple wire while trying to start it, but you need to check it when it wont start. If you dont have power, you need an ignition switch.
You need to have the theft deterrant system hooked back up or you are going to end up having alot more problems. Not sure how they could have disabled it in the first place. If they really did.