Posting this in electronics as well for exposure.

Car: 2003 Mustang GT

I recently had my keys stolen out of my car. I had the locksmith come by and reprogram two new keys for it. After that was finished he tried to start the car. The engine turned over fine but wouldnt start at all. A few tries later it started doing my recurring problem.

Here is what happens:

You try to start the car and the starter engages, turns the engine maybe 1/16th of a turn and stops. This isn't a normal click as in when the battery is dead and the solenoid clicks. The starter engages, bumps the engine then stops. The locksmith dumbly suggested the battery was low so we put jumper cables on it and voila, car starts. I knew that made no sense because immediately before the problem it was spinning over fine. Well he left that day and a couple of days later the problem happened again. I placed the jumper cables on it and it starts.

We did this for a couple of weeks every other day or so. One day I thought, well it can't be low voltage because the battery is fine. I've already cleaned the cables and posts etc. So I placed the cables on my battery and "sparked" the open ends.....Car then started. It started after I sparked the other ends and didn't even connect them to another battery or car.

Also one day it did this I placed a battery charger on it in the 50 amp start position and that wouldn't start the car.

Again, my battery is fine. My starter is fine.

The theft light DOESN'T flash rapidly during any of this. Once the car starts the theft light goes away.

I've tried unlocking and locking the door several times to no avail.

Anyone else experienced this?

 

PATS will either let the car start (it will turn over, but will not start if PATS is blocking it), or it won't. It wouldn't act flakey. The THEFT light either blinks rapidly, or stay on if PATS is blocking the starting or if there is someother problem.

What is the battery voltage while cranking the engine? What you describe sounds like a low voltage problem. If the battery were shorted internally or sulfated, jumping it or "sparking" the terminals as you did can often blow through the short or sulfation and make things better for a short while.

 

+1 sounds like your battery was low. If the voltage is low enough it may crank. but if theres not enough voltage at the modules such as pats or pcm etc. they will not operate correctly. cuasing your symptoms.