Dead 7.3!!!! Please Help

[bryceba]

So just as a precurser I had starting problems about 2 months ago and replaced by GPR which was actually cracked in half hence the hard start problem. Now we get into the real problem:

I started the truck this morning and it started great! Fast start, good battery power, no smoke, etc. I get to work with no problems and shut the truck off.

I get done with work about 10 hours later and go to start my truck. It hardly cranks and my battery gauge shows that it is on the line just above 8 which I suspect is about 10 volts. I figured I may have left a light on but no I really second guess that. I had my sister jump it and it started with much convincing. It would start for a sec and then die. While it was hooked up to the jumpers I noticed a cylinder shaped object behind the passenger side battery that was making a fast loud clicking noise.

Once it was started I unhooked the jumpers and shut the hood. I then pulled out of work watching the battery gauge and it was steady but as I accelerated harder I noticed that it was going down (ps, when I very first got it started and running the battery level appeared to be at normal level, halfway between 8 and 18). It continued going dow for about a mile until it I shut the engine off because my ABS light and Airbag light came on and my gauges started tripping out.

I let it rest for a few minutes and then jumped it again and that cylindrical shaped object was still ticking. It started and idled at normal voltage and stayed consistent until I again started moving. It lasted a bit longer this time and still continued to die. The lights and gauges lit up the same and I noticed that my headlights were dimming. My RPM gauge never died but the other gauges were spazzing out and eventually all shutoff as my voltage hit the 8 volt mark. The truck was still running but seemed to have some lag between the time I hit the gas and when it would pick up and respond. I have NOOO idea what could be the cause of this and I have no idea how to even troubleshoot the problem. Can I please please get some help. Thanks so much. I just need to get it working so I can get my baby to my sisters safely instead of a scary jeep.

[SCUFFY828]

sounds like alternator is taking a dump and have both batteries tested , the clicking noise is hapening because of the low voltage , they get confused when the voltage gets really low

[bft blue oval boys]

sounds like altenator to me too. thats exactly wat my old truck did when the altenator went bad on it. good luck

[bryceba]

but would an alternator just go out all of a sudden. I mean my batteries have been charging fine everyday and it started just fine this morning and was dead 10 hours later. Also the batteries are less than a year old. Why would the RPM gauge jump while I was cranking the starter?

[bryceba]

oh yeah and it was just the cylindrical shaped object behind the passenger battery making any ticking noise and it was making the noise even when I wasnt cranking the truck. It looks like it has vaccuum lines going into it

[bryceba]

I dont mean to doubt what was said. I just have small pockets so I just want to make sure

[bryceba]

bump bump bump

[highraven99]

take the alternator off and have it test at a parts store. they should be able to tell

[bryceba]

I just had an idea. What if my serpantine belt snapped about a mile from work on my way yesterday? It was cold enough and I was going fast enough that my engine temp probably wouldnt have risen at all. That would make sense on why I have never had any alternator problems. I will check when I get home and also test my alternator. Thanks guys

[ianstew]

you'd def know if your belt snapped.....