I own an 87 4runner, 22re engine. It will not start on its own, but will start when jumped from another car. It has a brand new alternator and battery, sometimes the alternator charges, other times it does not charge. Today i had it checked it O'reileys and they told me the alternator was charging at 14 amps and the battery was 68% charged. I drove to a restaurant and parked it, when i came back out it wouldnt start, after jumping it with another car it ran fine, i tried to go back to O'reileys, by time i got there the battery was damn near dead and not charging at all. This has happened multiple times in the last week and a half. Anyone have any idea as to whats going on?

Both your "new" batt or alt could be bad. The batt should be about 12.6 V engine off a

Battery. If the alt. is dead, the car should still start with a fresh battery.

1. Start the car, then remove the positive battery lead. If the car dies, it's the alt.
2. Try another battery, and see what happens.

You really think its just the battery/alt? Like i said i bought them both brand new less than a week ago. Had both tested by oreiley and they told me both worked perfectly fine.

And do you think that both the alternator and battery might be shitty? Hence the lack of starting AND lack of charging... that seems like terribly bad luck to me lol.

Check for oxidation of your battery cables. Look under the insulation for greenish white powder.

Don't know, but both are easy tests. The thing that doesn't line up for me is a "new" battery with a 68% charge. Obviously it can't start your truck, but other power sources can. So.....?

just because they are new does not mean that one of them are not bad . A friend of mine bought a battery got it home put it in his truck and the truck wouldnt start took it out and checked it it was dead took it bad they tested it and it had a bad cell in it right off the shelf So unfortunetly .

I would also check for broken door switches for the dome lamp, I've seen these break, and drain a battery, even with the dome light off, it keeps the computer awake, of course these are old enough they may not go through the computer, but it's worth checking.

Mike

With the battery cables off, check for continuity from the alternator connector back to the ecu and to the battery. Then check ohms at the connector, if you have a book on the truck it should tell you the acceptable ohm range. Also check all of your grounds. Do this with a continuity tester also. Put the red lead on the neg side of the battery, and the black lead on the body somewhere where metal is showing, you may have to scratch it a little to make sure. You should have continuity there. Also check from the ground on the alternator connector to the engine some where. Continuity should exist there too. Do all this after you have made sure the battery is good and the alternator will keep the engine running with out the battery hooked up.

You no man my 87 is doin that same shit right now and I figured out tonight if you put it in 5th gear and push the truck forwards and back it like pops the starter and starts right up. Auto zone told me my battery and alt. Were good too. I am goin to mess with my starter and the cellinoid tomorrow I think that will fix it ill let you no.