We've got a 2006 Mustang 6cyl with 88K miles on it. About 5 months ago, it began having an intermittent starting problem. Turn the key, the dash lights go on, but the engine wouldn't crank - just clicking. After a couple of tries, it would start. And other times it would start just fine on the first try.

We took it to the Ford dealer thinking it was a starter and they said it was just a bad battery. We put a new battery in and everything was fine for the next 5 months. Now, the problem is back. Sometimes it starts on the first turn of the key, other times the engine doesn't crank at all. We'll keep trying and eventually it will start.

I decided to troubleshoot the problem by trying a new battery, since that seemed to fix it last time. Nope, the problem is still there.

I know it sounds like a starter, but it just seems strange that we had the problem months ago and then it went away with a new battery and now it's back again.

Does anyone have any ideas? Thank you in advance.

 

Sounds like you might have a bad alternator, our mustangs OE alternators are notorious for shoddy reliability, especially the earlier model years.

Get yours tested, I believe autozone/napa/o'reillys does it for free.

 

Throw some jumper cables on it.
If the problem persists while being jumped it's the battery/alternator. (Rules out the starter)

Autozone etc can test batteries, starters, alternators, etc. while they're still on the car...
but they aren't always accurate.