[noyz25]

Most of the time it cranks but sometimes it dont. And push starting a mustang by yourself is noooo fun.

[whiteboycustom]

do u have headers on ur car???i know once i put my long tubes on the starter wouldnt want to turn over once it was hot

[HMUSN]

heat soak ?

[nba1341]

the solenoid will make a little smoke come out of it

[TENGRAM]

if it cranks too slow to start it sounds more like a cable problem. if when it doesn't start it doesn't do anything at all it could be a tfi issue.

[White Thunder]

advance auto buddy

[ChrisJ]

When it doesn't start does it click or anything?

Just in case you guys dont know the starter solenoid is on the driver side fenderwell...Not that bad for heatsoak...

[noyz25]

No click no nuthing. And yeah when it does start it goes like crank pause crank pause VROOOM. Could that be cuz i have my timing at 14 advance?

[nba1341]

have you tried banging on the solenoid?

[Speedstang302]

Originally Posted by noyz25 No click no nuthing. And yeah when it does start it goes like crank pause crank pause VROOOM. Could that be cuz i have my timing at 14 advance?

whats done to the motor..i'd say if no bigger cam i'd do 12* i run 14* w/ f303 cam and 1.6's

[nolife]

It could be either. Even with some troubleshooting, there are problems with both that will give the same indications. I will venture a guess though that if you hear absolutely nothing at all, not even the solenoid click when attempting to start, it is something between the ignition switch and the solenoid and not the starter.
You can just about narrow it down by trying a temporary jumper.
Two words of caution
1) Put you car in N if 5 speed or park if auto because doing this jumper thing I am describing bypasses the N safety switch and the clutch switch so be careful, double check it, really.
2) Keep the keys out of the ignition while doing this and just in case, take the rotor out as well to keep it from actually starting.

Place a small jumper wire between the positive on the battery and the small threaded stud on the top of the solenoid. The car should crank and keep cranking the whole time this jumper is attached. If you do not hear the solenoid click, the solenoid is bad or the ground for it is bad. If the solenoid clicks but you do not hear the starter engage, it is the wiring to the starter, the starter itself, or it could still be the solenoid.

If the solenoid clicks and the starter turns over fine then it is something from the ignition switch to the solenoid which includes the clutch switch.

If you are not sure what small screw terminal on the solenoid I am referring to attaching the jumper on, look through a manual or a wiring diagram somewhere. Don't just start touching things with a live jumper wire attached to the the battery.

Being an intermittent problem makes things a little tricky. The next time it does not start for you, listen for the solenoid click, that is the major thing for narrowing it down. There are a lot of things that click when you turn the key, have someone close to the solenoid to make sure.
Report back your results and we can take the next steps!

Don't forget to put the rotor back in

[BigBlockFairlane]

The whole system needs to be be looked at. 1st, the solinoid is cheap. Just swap in a new one.

I personally bet the battery is going or you have a bad ground.
Try hooking a set of jumpercables from the block to the frame when the problem happens and see if it fixes it. If yes, bad ground.

Also a bad voltage regulator or alternator will keep the battery from charging. (all my cars are pre 1971 so forgive me if the VR is electronic or part of the computer or something)