loss of power, engine shut down and no restart

[doug25427]

Hello all,
My son owns a 2002 4.6 Mountaineer with problems that have me stumped.
Driving at 40mph it began to lose power and then the engine shut down. It would not crank much less start again. A loud click could be heard but no starter engagement. They towed it to my home.
I found a lose ground connection at the battery. I fixed it and began charging the battery. In 30 minutes the engine started and idled well. I let it idle another 30 minutes before it was to be driven home. Within 4 miles of my home the engine did the same thing again. Lost power, shut down and would not crank.
The next day I installed a new battery, started the engine without incident and checked for charging voltage. It read 14.6 volts.
Once again within a few miles the same exact problem occurred again. The starter clicks but nothing more. I checked the battery voltage at 12.5 volts.
I am at a standstill wondering where to begin to diagnose this problem.
I have removed the alternator but I have my doubts this is the problem. To my way of thinking the alternator wouldn't be the cause of the engine shutdown within a few miles of the battery being replaced with a new one. Being I have the alternator removed I'll have it checked but I'm willing to bet it is OK.
Any ideas would be greatly appreciated.

 

[SexyExy]

If the alternator is producing power which it sounds like it is if charge volatge is 14.6 double check all connections from alternator to battery, I
Had a similar issue with my 4.6l mustang, loose battery connection would come loose on bumps and kill the engine

 

[Everdream]

when you check charging Voltage are you checking at the alternator or the battery? if at the alternator than you have some problem between there and the battery like the above poster said.

 

[doug25427]

when you check charging Voltage are you checking at the alternator or the battery? if at the alternator than you have some problem between there and the battery like the above poster said.

Thanks for the reply. Both battery connections are clean and tight. I always measure charging voltage at the battery.

 

[SexyExy]

Make sure all of the smaller wires that feed into those connections are secure as well, also even if the wires appear to be clean going into the connector there could be corrosion inside the clamp that holds the wire to the terminals that might not be visible without dis-assembly.

Also just realized that you said battery was 12.5 after no start, you probably do not have a problem with the alternator... Battery voltage would certainly be lower if the battery were discharged. Additionally it is making at least a weak connection because it will click if you try to start it, the wires just cant carry enough amps to turn over. So yeah, check for corrosion inside terminals or wires that are not securely joined together...

 

[doug25427]

Make sure all of the smaller wires that feed into those connections are secure as well, also even if the wires appear to be clean going into the connector there could be corrosion inside the clamp that holds the wire to the terminals that might not be visible without dis-assembly.

Also just realized that you said battery was 12.5 after no start, you probably do not have a problem with the alternator... Battery voltage would certainly be lower if the battery were discharged. Additionally it is making at least a weak connection because it will click if you try to start it, the wires just cant carry enough amps to turn over. So yeah, check for corrosion inside terminals or wires that are not securely joined together...

Advance Auto checked the alternator and found it to be bad. This surprised me too. Twice I have drove to a repair shop with just the battery after losing the alternator. Once on my Harley and once on my pickup. I doubt a bad alternator is the only problem.

 

[Everdream]

I do too, Like I said, because of how you found that truck, I'd check everything.

 

[doug25427]

I do too, Like I said, because of how you found that truck, I'd check everything.

Thought I'd let everyone know the motor is locked up.
We put on a new alternator with a new fully charged battery and it wouldn't crank. Removed the starter to have it checked and it was OK. Checked all of the starter wires and they were OK. Tried to turn the motor over with a draw-bar on the crank and couldn't get it to budge.
Luckily the parts store took back the alternator for a full refund.
I've been working on cars a long time and never have I seen this. I jumped this car once and it ran 4 miles before it stopped. I put in a new battery and it ran another mile before it stopped. No noise at all from it either time. I've never seen a motor stop like this without giving some sort of sign.
Anyway... thanks for the help.

 

[Everdream]

I've seen it once on a car with a clogged oil filter where it just stopped running instantly. Sorry to hear man, time to buy yourself a new 2nd/3rd gen ex though! Excuse available.