Discussion in 'Fox 5.0 Mustang Tech' started by Travis R, Jun 15, 2014.

  1. Recently my mustang has had some issues. It would start right up if i let it sit over night or for a few hours, but if I go for a cruise or drive around for a while and shut it off. When I go to start it back up it will want to turn over but it won't for about 5 seconds. It finally just went out so I replaced the alternator and it started running again fine. But after I run it for a while it will have a very weak start. Any ideas on how to fix this or what is going wrong?

    1990 5.0 hatchback
    BBK 75mm throttle body
    BBK headers
    K&N intake
    MSD ignition coil
    Mangaflow exhaust with H pipe
  2. Had a similar issue, it turned out to be just a weak battery. I had a newer alternator on it, but on a hot start, it would be so weak that she almost wouldn't start. I was over-thinking the problem, until I was sitting for about a half hour one day with the radio on after work, and it was enough to kill the battery to where she wouldn't start. New battery, no more hot start problems! Hope this helps, and good luck!
    Travis R likes this.