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My QX4 has me stumped

I’ve had the alternator and starter tested twice,new battery.its a 97infiniti qx4 and it won’t hold a charge.the weird thing is,I have too waits day or two after I charge the new battery (which I replaced twice thinking it was the battery),then it will run for almost a day and then it just dies.and if someone tries to give me a jump,it will not charge and fire over.I have to get it towed back home and wait a day or two.(the wrecking companies are getting to know me very well lol).I’ve checked under the vehicle for any wires that are not suppose to be touching each other.so now I’m stumped,does anyone have a clue or have had a similar problem.please help its my only car that I have at this time

Sounds like there might be a drain on the battery when the vehicle is turned off.

And/or some battery/alternator cables in need of replacement.

Alternators can test good and not be. A scantool while driving could tell someone what kind of voltage the PCM is seeing.

You say the battery won’t hold a charge, but then there’s a mysterious 1-2 day period after you charge it where it will start? You need to give an actual description of all of the car’s symptoms. You imply that it will “die.” Is that while it is running? Then what? Do you actually measure the battery voltage? What is it? Presumably it also won’t start sometimes. When it doesn’t start what - exactly - does it do? You turn the key and…

"if someone tries to give me a jump,it will not charge and fire over"
The simplest hopeful solution would be to clean the ground connections and check the cable from the battery on the vehicle probably on the engine block. If that does not work then do the same for the Positive. Then start working your way up to more expensive solutions.

Do you get lights and radio etc. when you try and start it?

Ok thanks for all the reply’s,and I will go into more detail.I have replaced both cables and it dies when I’m driving,I’ve had people try and jump it before and after I replaced the battery and cables.so what I have to do is tow it home/disconnect the battery/let the car sit/charge the battery put it back in and it fires over for about a day ot less.and like I posted before both alternator and starter were tested at AutoZone and O’Reilly twice.and both times I asked them the same questions on there testing machines,from what cigroller had posted.it sounds like either there machines don’t do a proper testing like they claim they do.or there knowledge on alternators is not that good.I’ve even gone as far as making sure all the wires from the alt/starter/battery are good and well insulated.and again thanks for everyone help

Have you put a VOLTMETER ON THE BATTERY? When you say it wont start…do you get ANY sounds when you turn the key to run? Any lights?..I think MikeInNH hit the issue SQUARELY on the head…time for a parasitic loss test…

If you want to try something that you can do yourself… Grab a voltmeter… Remove your batt cables like you do when you charge the batt…and CHARGE the batt… Measure the voltage… Do it 3 x actually…

THEN…hook up your batt cables with the key OFF>…measure voltage…Measure it again…and again 10 min later…again in 5 minutes

Is it dropping? Probably…

NEXT I want you to remove the 12V HOT wire from your alternator…it is attached by one single nut on the back of the alternator… Once it is off the Alt…TAPE IT UP… and measure your voltage again… and do it several X at 10 min intervals… Did the voltage level off and hold steady? IF SO>…its a short in the Alternator…

EZ tests to do yourself even if you are not a mechanic…You have a few tasks to do for homework…Let us know the results and we will go from there…

Blackbird