need some tech help please

[tryinkeepup]

when i start my 1990 gt the car starts fine when its been sitting for awhile and its cool, but once you start to drive it around and you shut it off hot it acts as if the battery isnt giving it enough juice and if you hold it it will start but it takes awhile to turn over. and the battery is brand new, so what could the problem be?

 

[90limited]

My guess is the ground cable needs to be cleaned or replaced were it attaches to the block. If your car has a smaller ground cable along with the big one, the small one will get hotter then heck when this happens...

 

[rd]

In order, I would remove and clean the battery cable connections, both at the battery and at the other end, particularly the battery to ground.

If this does not make a difference, clean and tighten the power cable from the relay to the starter motor.

In the meantime, if you have a voltmeter, check that the alternator is putting out 13 or more volts at idle and above. If you can, with an ohmeter, make sure the cables are ok, especially twist and wiggle them to see if that changes resistance.

If the alt is working and the cable cleaning and connection tightening did not fix or improve it,
I would change the battery. For the last 20 years, every time but one that I have had a slow start issue on a Ford F150, Mustang, or similar setup, a new battery has fixed it.

 

[coops93meangt]

Depending on where you have your battery mounted you may need to look at running a larger gauge battery cable.

 

[noneck134]

I had the same problem once in my old stang. Then it got to where it would not start until it cooled off. Turned out to be a bad starter. Once it heated up it wouldn't start.

 

[tryinkeepup]

thank you all for the help i appreciate it alot

 

[2000xp8]

I had the same problem once in my old stang. Then it got to where it would not start until it cooled off. Turned out to be a bad starter. Once it heated up it wouldn't start.

Ya, i had the same issue.

If the battery cables are old, i'd do them first, they aren't all that expensive. Then i'd look to the starter.