My 1997 Taurus has symptoms like a bad battery or alternator, yet I've
replaced them both and still have the problem. The battery isn't
charging and won't start the car, especially after driving the car for
a while. A jump will get it back up to where it will start. Also, if
the car sits for a while it will start. But when running, the
headlights are bright and there seems to be enough power.
Plain 3.0L EFI engine.
Battery voltage - not running, blower and lights on high = 11.9V.
Battery voltage while running 14.6 V.
I can't measure current draw easily.
Started cold this am fine w/lots of cranking power.
Belt seems fine, battery cable connections clean and tight.
Maybe a hot start issue?
Place one lead of a voltmeter on the negative battery terminal, and the
other on a good ground point on the engine. Check to see if there is a
voltage drop across these points WHEN the engine is cranked. If there
is, there is a corroded (poor) connection for the ground cable. Do the
same for the positive lead, only use the starter battery terminal
instead of ground and the + battery lead. The same thing applies should
there be a voltage drop of any substance.
You are going to need to take some measurements. What is the voltage
on the battery terminals while the car is running? How much current is
being drawn from the battery while the car is off?
Is the belt for the alternator loose? Are your cables to and from the
battery clean and tight?
Turn on the head lights when it won't start. Are they bright?
Now, crank the motor with the lights on. DO them dimm a lot
when it won't crank over?
CHeck the ground from
the battery to the engine block. If the
battery cables look suspicious, replace them.
I had a bad solenoid on my 93 which caused an intermittent no
start. It was a cheap rebuilt.
I'm going to make a wild guess and say bum battery cable or ground. I had a
cable die once right where the cable entered the clamp. It looked perfect
but caused symptoms like you describe. After I replaced both battery cables
I peeled back the insulation and found heavy, heavy corrosion. A good tug
seperated it completely.
You may also be seeing the signs of a dying starter, they get weaker if they
get hot. I'd check, or even better, disconnect all battery type cables,
clean, and reassemble first. Starter failure doesn't happen like that much
Hope this helps! PoD
It was the starter. It seemed to run okay off of the engine but
sounded funny. Took it to AutoZone and they put it on their tester and
it PASSED! But the guy said it sounded weak, and it did, compared to a
new starter which we also tested. Got the new starter and that solved
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