Mysterious Problem Help Needed! ⚠️

[4thgenblake]

Online mechanics,

I just had my battery replaced a couple days ago. After installation, the truck immediately felt weaker and didn't RPM idle as high/hard as it did with my old battery. Vehicle started up every other time (after being instructed to by the autozone guy) The other times it just wouldn't even turn over for some reason. I thought this was just the computer reconfiguring itself.

A few hours later, all electrical is out. No unlock feature on doors, NOTHING. Waited 10 mins, turned key and got a faint connection again enough to start. If I start it too quickly it starts and dies within a few seconds. I had to keep the switch on for a little and then start it (as if I was aloud 1 start every 10 minutes) so I thought the alternator may be bad

Checked both battery and alternator with a electrical tester and both seem to be putting out the right amount of power?

Here's where it gets tricky:

Started the next day fine with weak start-ups (yesterday), until I started the truck too fast again last night and it died completely. Truck will not jump start whatsoever even with another V6 hooked up to it. Not even dash lights. It's like the battery lost all connection to the vehicle. It has a new positive terminal connector and negative is in good shape. Ruling out a bad battery.

Follow me here, this morning is showed a faint open door light for a few seconds then it went off. Truck was losing the little bit of electrical "oomf" it harvested over night (it had none when I was trying to jump it last night) No response from truck now.

I have narrowed it down to being the starter, ignition switch, alternator, or fusable link/relay for main power? With the research I've done, what further testing can I do to track down the problem?

I will purchase a multimeter or what have you to check before having it toed to the dealership for a further diagnostic test. I know it could be a number of things unless you see a pattern here?

Thanks

 

[Trumpet]

Bring it back to the installer. They must of screwed up.

 

[TowMeOut]

Just curious....what does "new positive terminal connector" mean? Did you install a new OEM connection on the existing cables or is this one of those emergency clamp-on pieces? Those tend to build up corrosion between the wire and clamp in a remarkably short period of time, especially here in FL.

Everything you describe sounds like a very poor/intermittant connection to the battery. Grab a wrench and tighten all the connections one last time, especially the grounds.

It's a bit of a long shot but "new" battery doesn't necessarily mean "good" battery. Some shops fail to rotate the stock and a battery that still says 12.6V can be bad because this is a "surface charge". Turn your headlights on for 10 seconds then try checking the battery again. If you see a significant voltage drop (probably more than .5v) then the battery may be bad. You can take it to about any parts store and they'll test it for free (or back to your installer).

Another "shadetree mechanic" way to test is easier to do at night. Turn on the headlights then work your way around the harness and wiggle or tug on the cables. If you see the lights brighten/dim then that's your likely problem area. The connections to the starter and engine block are kind of a pain to access but they could have worked loose over time (worth a shot).

Good luck...electrical gremlins are a pain!!

 

[Atlanta_man]

I once had a loose ground cable at it's (hidden) connection to the body - pulling on it and it would start.

I'm betting on a bad connection somewhere along the battery + - cables, maybe the fusible link in the + circuit.

 

[Drunner97]

After a battery change you have to let the ECU reconfigure your idle so it will start out low and fix itself after about 5-10 mins of driving. My guess is that the battery wasn't fully charged to begin with and you just drained it back down enough to where it wouldn't start, but sitting for a period allowed it to regenerate enough power. I ran into a whole slew of issues a couple years ago and it turns out that the alternator doesn't actually charge below 600 rpm. So at a low idle you're just draining the battery until it fixes itself.

 

[Legender]

My vote is on the battery. Did they measure before the install?
The only thing you changed in your system is the battery, so I'd look there first.
Agree, you need some high RPMs to charge up the battery... idling won't do it.

 

[Jefe]

The PO didn't state why he originally replaced the battery but I'm guessing these problems occurred after the install, So I would start with the new battery.
Load test your new battery. Like previously mentioned, New does not mean its still good. If it checks out ok check all connections positive and negative. These trucks don't have electrical problems and usually when they come into my shop with situations like this its due to mistakes made on the install

 

[4thgenblake]

Interesting feedback... I forgot to mention that my previous battery was 4 years and counting out of a 5 year warranty old. They honored it and gave me a newer model off the shelf with same part number , CCA etc.

Silly fetch, do you think the two different metals that make up the positive could do with it? Bronze and copper/lead?

I think the battery could be a bad one off the shelf anything is possible I guess. I will try that first before I leave with an alternator instead.

 

[4thgenblake]

Interesting feedback... I forgot to mention that my previous battery was 4 years and counting out of a 5 year warranty old. They honored it and gave me a newer model off the shelf with same part number , CCA etc.

Silly fetch, do you think the two different metals that make up the positive could do with it? Bronze and copper/lead?

I think the battery could be a bad one off the shelf anything is possible I guess. I will try that first before I leave with an alternator instead.

I noticed I had tape over the label.



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[TowMeOut]

The dissimilar metals aren't a problem. Your cable ends were silver colored before but corrosion has eaten off the plating, uncovering the copper. Speaking of corrosion....was the previous battery and clamp seriously corroded? That will often indicate some over-charging problems.

Don't run off and get an alternator yet. Your truck will start and run just fine without an alternator at all, the battery just doesn't get recharged. You need to figure out what that the starting/running issue is first then you can worry about the charging. Hopefully they'll turn out to be one and the same.

 

[4thgenblake]

When the battery is connected my dash lights come on faintly and flicker indicating there is little electrical connection. Does it sound like the alternator isn't connecting with the battery to keep it charged?


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[AuSeeker]

When the battery is connected my dash lights come on faintly and flicker indicating there is little electrical connection. Does it sound like the alternator isn't connecting with the battery to keep it charged?


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Not necessarily, but there still could be an issue with the alternator, either the alternator is connected properly or it's not, if no one lossen the
conections at the alternator it should still be connected properly, BUT if the alternator isn't connected properly you wouldn't have any electrical
functions because the alternator is part of the battery/charging system/circuit.

The only way to check the alternator is to properly charge the battery with a good battery charger, then go have the alternator checked at your
local auto parts store with the proper testing equipment, charging the battery properly would also tell you if you have other issues since in
most all cases it would allow the vehicle to operate properly even if the alternator is or going bad until the battery voltage gets too low for the
system to work correctly.