Mechanics 101 [bonehead] - Don't trust a new part!

[1986F150Six]

This is to help other less than stellar mechanics, like me.

Recently, I have been driving my wife's "old" car, a Pontiac Aztec. We have had it all but 2 years of its life and it has been good. Last week, I drove it to work and all was well. When quitting time arrived, I inserted the key and NOTHING... not even the ding, ding, ding associated with having the key in the ignition switch with the door open. A friend jumped me off and I drove approximately 8 miles to town, made an errand stop, restarted and drove ~3 more miles to the house and shut it down. The next morning, NOTHING!

By the way, the car had a good quality battery which was ~3 years old. I pulled the battery and did a visual of the cells. All were properly filled and clear except for the one nearest the positive terminal, which had some gray flakes floating on top of the electrolyte solution. I connected the battery charger for a few hours and carried the battery to be tested. It failed.

I bought a new battery with 800 CCA and promptly installed it. WOW! Everything went crazy! I had lights illuminated on the dash which I had never seen. When trying to lock or unlock the doors with the "lock button", there was feedback through the speakers?? The car could not be taken out of park. Nothing worked. Out came the new battery and I took it back for testing, yesterday [due to work schedule]. Well, it had 12.1 volts and completely failed when the load was applied.

Back home with the 2nd new battery and installed and WHAM, it started and all is behaving as it should!!

By the way, before leaving with the replacement new battery, I insisted that it be tested. It passed! This battery is rated @ 850 CCA @ 32F and demonstrated 920 amps @ ~70F.

[Gary Lewis]

We've all "been there, done that" in one way or another.  But I've never had a bad battery right from the get-go.  Glad you got that sorted.

By the way, do you have a keep-alive battery?  I have a plug and a 9v battery that goes in the cigarette lighter to keep the settings alive while you change out the main battery.  Comes in really handy when you have lots of pre-sets that are a pain to redo.

[ArdWrknTrk]

That's ingenious Gary.

I have a 9V with some alligator clips that I connect near the fender relay for the same purpose.

[PetesPonies]

Batteries are oh so simple, but can act very strange. here's a real story .  . . . in the 80s I had a battery that was acting up, would work fine sometimes, other times be dead. Not wanting to buy a battery just for the heck of it, I tried a few things and wanted to make sure it was truly the battery and not a strange drain somewhere. To cut to the chase, one times while testing or such, I hooked a 12V work light to the battery, which was out of the car. The light blinked on and off, at a steady time interval, just like it had a timing circuit attached  :) My jaw dropped,  .  I bought a new battery.

[Gary Lewis]

Yes, batteries can act strangely.  Haven't seen anything as bizarre as a light blinking on and off, but I have seen the voltage change abruptly.  When we had the '72 F250 we had a 9 1/2' self-contained camper on it. New truck, new batteries, new wiring. And I've seen the lights change brightness many times in an evening, from bright to brighter and back to bright.  All of the lights would do it at the same time.  I checked the circuits and connections out completely - there were no bad connections.  But the voltage would change so quickly you could see the light intensity change.  Like maybe bubbles were forming in the electrolyte and then letting go, which changed the voltage.

I don't know what the cause was, but it happened and frequently.