I got a 1986 rx down the street from my house for $600, i want to get it but the battery wont stay charged. she got a new alternator and new battery, and it started but as soon as I took the jumper cables off the battery just dies! what could it be?! Please Help ~ thanks

 

Check the wiring between the battery and alt (big cable on top of the alt, llops through the harness, then back towards the batt)...

Check the 2-pin plug on the back of the alt...

Check for any blown fuses...

What's the voltage on the gauge when she's running?

 

havent had her started long enough, i was just trying to test drive her..

Well when the battery is connected to the jumper cables it shows 12 volts like normal but as soon as i take the jumpers off it starts to die again...

 

Sounds like the ALT might be disconnected and/or the battery is drained. How are you connecting the jumper cables? Directly to the terminals, or pos terminal and body? Make sure the battery is hooked up properly. Use a voltmeter and check the voltage across the terminals of the battery. (should be at least 12 volts.) Use your meter and check resistance between the negative post of the battery and the body, then the negative post and the engine. Should be almost 0ohms. Worst case it should be less than 10 ohms. Any more and you have a grounding problem. Remove the pos battery cable, then check the resistance between the big terminal on the ALT and the positive battery connecter. this should also be about 0 ohms.

Good luck