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Truck starts then dies


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Like the title says my truck starts then dies, but only after a jump start. It will not start under its own power. The starter clumsily cranks once or twice and then starts rapidly clicking. The starter made that noise a year ago so I swapped the battery that I’m using now. To jump, I’m using one of the portable battery packs so once power from it stops the truck stops as well. 

This started happening this morning after I changed the oil, filter, air filter, and fixed a vacuum leak. The last time I had the truck running was about 2 weeks ago with a vacuum leak and I had to tap the gas to get it to start (this was after charging the battery, replacing fuel pump and filter). When first attempting to start it slowly cranked. It wasn’t consistent. I tried charging the battery to 12.01 volts and the same issue still occurred. I then took my battery packs and jumped it which did work, until about 30 seconds in and then it would sputter and die (the first round I had 3 consecutive starts 15 seconds apart). I tried again after a couple minutes and neither battery pack I owned would even start the jump start sequence (it just said “connect to battery” on the LCD even though it was connected). My gauges never read more than 9 volts in the brief window that the truck ran. The fuel pump also noticeably stopped priming when in the start position although it was priming this morning.
 

My hunch is that either the battery is  bad despite being a year old, the alternator is dead, or something else entirely that I don’t know. I’m leaning towards the alternator simply because of the low voltage after jumping, as well as similar experiences with my daily, but is there anything else I should check first? I have not tampered with any wiring. 

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22 hours ago, Pete M said:

a bad battery can suck the life out of a decent alternator.  but both can be checked for free at an autozone or the like. :L: 

Ok so here’s an update: took both the battery and alternator to autozone. Autozone says the battery’s bad and the alternator is fine. Got a new battery and put it in and the truck fired up under its own power but then died again after startup. So it’s definitely not the battery. If it wasn’t building fuel pressure then I think it would just continue to try and try to start, but I’ll test it anyway when I have a chance. Not sure what else it could be.

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Dying a few seconds after a perfect startup is very likely to be related to the ballast resistor, as cruiser says. 
 

In regards to your battery, obviously you’ve got an answer on it now, but for future reference, 12.01V is a very discharged battery. They’re only nominally 12V, actual full charge voltage is around 12.67V. By the time it’s down to 12.01 it’s below 50% charge. There’s also something batteries do to fool you, they’ll read somewhere between actual voltage and the charger voltage when you pull them off the charger, we call that “surface” charge. You generally don’t get a good voltage reading off a battery until you’ve thrown a small load at it to knock that down. 
Batteries brand new off the shelf at the parts store aren’t guaranteed fully charged, either. Although that’s not a huge issue here. 
 

I’ve seen jump start attempts blow charging fuses. The HO has two 60amp alt fuses in the under hood box, but I’m not familiar with the Renix setup. Something to look into if you’re not getting 13+ volts out of your charging system once it’s running, but look into the ballast resistor first. If you’ve got enough charge in the battery to run the starter you should be able to run everything else on the truck too. 

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So good news, spraying some contact cleaner on the brown and black terminal ends and bypassing it with some copper wire fixed the issue! Now, are there any good universal ballast resistor replacements that are available at places like autozone or advance auto? Would prefer not to wait a week for a rockauto shipment......

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