Hey guys,
I'm just gonna get right to it.

I have a 2001 v6 mustang.
I'll start off by saying that the car was used when i bought it last August.
The problem that I am having with it is that sometimes after driving the car around and shutting it off and turning it on again(by that i mean i drive to one place, shut it off, go do my thing, come back, turn it on, take off to my next destination, park, shut it off, turn it on, repeat), it won't turn on. When i say that it won't turn on, i mean, that i turn the key, the lights all come on, but when i put the clutch in to crank the car, i get nothing. Whenever this happens, i normally take the key out and put it back in, trying to start the car over and over again, but the car just doesn't start. I've learned that whenever i'm in this situation, "jump starting" it seems to turn the car on every time.
That being said, you'd think the battery would be the problem, but it's not. I have a brand new battery and i had advance discount auto parts run a battery test on it and the test results show perfection. I also got a scan for my check engine light done but the only issue that comes up on the scanner is that my intake manifold control runner valve is messed up. After doing some research on the IMCR i found that a messed up IMCR only makes your car go slower/sluggish. It doesn't have anything to do with the car starting.

Another thing that i've tried replacing is the Starter. I went with my father and bought a new starter and put it in but even after the new battery and the new starter the problem has continued to persist.

We've tried the chip-in-the-key thing and that isn't it either. The theft light doesn't come on. The only light that stays on is the check engine. But i already know why and i told you guys why. Like i said though, that doesn't cause the car to not start.

I've taken the car to the Ford dealership 3 times already and they kept it for four days at one point to see if the car acted up and they drove it around but apparently it never acted up. So i just picked up my car and drove it home.

My father thinks it's an ignition issue, like maybe a lose cable or something. I think it might be heat related(in the engine), because of the fact that this problem occurs after the car has been driven around for a bit.

The only patterns i've noticed after this problem occurs is:

1. If you jump start the car, it'll start and you can drive off.

2. If you leave the car sitting for hours, then come back to try again, it'll start.

I'm getting really tired of playing trivia with this car. & the fact that nobody i've talked to has ever heard of this problem(not even FORD, who makes the car), really agitates me.

So there's my issue. I'm hoping that all of the other mustang owners out there could help a brother out.

I know it's a really long post but more info than less info is always good!

Thanks!

 

Cooling down and jumping it indicate two different problems.

If you jump it and it works, I'd say you have an electrical issue (loose battery terminals, drained battery etc...)

Cooling down sounds like a fuel pump/filter or a dirty airfilter or bad IAT sensor.

 

could be a clutch or brake switch, it doesnt think the clutch or brake pedal are pushed in, so it wont complete the starter circuit?