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puzzle, won't start +

1050 6
Hello everyone, this is my first posting as is probably not uncommon, I have a problem.
I have a 2004, 154,000 miles. This is a strange problem, because it seemed that more than one system failed it once, or at least very close in time.
I was several hundred miles away from home (doesn't it always start that way?) and the car exhibited some weird behavior. At one point the automatic transmission would not shift even at about 4000 RPMs on a flat surface with no acceleration. I moved into semi automatic and then back into automatic and the transmission behaved normally. Later that night I was driving and on dry pavement my brake system, ABS, flat tire monitor, DSC lights all came on and the speedometer dropped to 0 mph; the headlights, dash lights and engine continued to function normally. The speedometer woke up after a few seconds and the warning lights cleared upon powering down and powering up the car.
Computer right?
A few days later, upon starting the car for the trip home, I noticed a gravelly sound coming from the front of the engine sounded like shaking rocks in a plastic container. Worried, I stopped the engine and immediately checked the oil which was okay. I restarted the car and the sound was still there but the engine was running smoothly. I was stuck and had to get home and began the roughly 300 mile trip. The car performed perfectly was getting very good gas mileage and took us 99% of the way home. I pulled into a supermarket and noticed that the gravelly sound was a bit louder. I stopped the engine and went to buy some groceries.
Upon returning the car would not start but would only give a couple of feeble turns with each attempt. I had thought the gravelly sound in the front of the engine could have been something like the alternator getting ready to go and this seemed to confirm it.
However, I could not jump start the engine either from another car or from two different AAA jump boxes, just got the one or two cranks and no more. I had it towed home, checked the battery voltage which was a hair over 12 V. I've had it attached to a trickle charger and the battery registers a little over 12.5 V but I still the same sluggish or non-cranking behavior.
So, did my alternator, computer, and starter all fail at the same time?
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Not even a SWAG?
(Scientific Wild Ass Guess)
I think it is your battery. As you will read in the link a battery that seems to be "almost" charged is perhaps only 50% charged.

The sound from the front of your engine is probably coming from the various belt pulleys or belt tensioner. Or, the water pump. If the water pump fails the engine will lose its coolant, overheat and blowup :). Or, if the pump seizes completely the serpentine belt will shred right off the pulley system and leave you stranded. The same outcome for the belt(s) when a pulley seizes. Failed belts and hoses are the number one cause of roadside breakdowns. Dead batteries are probably #2.

It would help to know when your battery was replaced (if ever) and when your belts and pulleys were replaced.

As you know there are many good diy types on this forum who will probably help you with their opinions of what is causing your problem(s).
My SWAG would be that a new battery and a check of the serpentine belt tensioner pulley and the deflection pulley is required.

Gravelly sound may have been dry bearings on one or both of those pulleys.

Computer is likely fine, just that the deep discharge on the battery affected it in a bad way.

A completely dead cell in the battery could have prevented the AAA boost from working.

Thanks to you two for chiming in.

It was the alternator, it was so bound up the starter could not spin the engine. Mercifully cheap fix and I can only assume that had the engine restarted the serpentine belt would have been shredded with the alternator frozen.
I think that is the first time I've heard of that problem. Have to remember...
reasonable solution

I did want to post the answer since it tied up all the threads pretty well. Charging poor leads to computer flurg, gravelly sound in front of the engine with otherwise smooth engine sounds leads to alternator fail, stopping car leads to cooling, leads to seizing of the alternator which places too much of a drag on the engine to spin with the little starter motor.
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