The car is an 88 Crx si. Just got it back on the road from a overwinter build.

The car ran mint 2 weeks ago when I took it for a few hour trip out of town, electrical system was fine.

2 days ago I start driving it again and noticed that after a while of the car idling and me turning it off an on (no driving, I was tuning idle and such) that the battery was getting weaker. Eventually the car didnt start

I figured my battery went dead or I got a bad one (battery was BRAND NEW 2 weeks ago). SO I grabbed the dinky small one out of my truck and threw it in and it fired right up. Went for a 30 min drive tonight without turning the car off and came home

Went out 2 hours later and the car wont start, barely has enough power to light up my gauges and start the fan.

So now Im stuck, the battery is brand new, could be bad but I swapped it with a known working one that I drive daily in my truck and it still killed it.

I also read that if you get the car running and then disconnect the negative battery terminal that if the alt is bad the car would die, well the car kept running when I pulled the negative terminal.

The alternator was replaced about 14 months ago, sat through winter, worked just fine a few weeks ago on my trip. but my battery isnt getting charged

The car is obd0 and the motor is a d16a6. I need some help on how to diagnose this ---- please. I need this car

 

1) take off alternator
2) go to autozone
3) have alternator tested.
4) have batteries tested/ charged for free

 

Thats not true, it depends how bad the alternator is, Also, you may need to check all the wiring again to make sure nothings fried or theres no shorts. Also, make sure you dont have a light or switch on somewhere that you dont know about draining your battery.

 

get a multi meter out, check batt voltage when car is running, if its under 13v alt is bad

 

The alt was a rebuilt unit

Is there a certain time when you have to check the power level?

Like if I fully charge this dead battery like im doing now, throw it in the car and start it up, will the atl still read the higher voltage?

 

just because its a rebuilt alternator doesnt mean its good.. i put a rebuilt alternator into my truck and it was fucked up.. i took it bacck and got another one.. and it worked fine...

 

yea def.ly check the alternator. I replaced the alter. on a corolla with a Kargen rebuilt unit and it went bad within a week, luckily it came with life time warrenty

 

OEM for the win. Stick a stocker new Honda one and let it last another 17 years without touching it .

 

I dont believe it is the alternator though because the car will run when you disconnect the battery when you kump start it

Meaning the alt is keeping the motor going

Its new and it worked a week ago and when i searched people said thats how you determine a bad alt

 

ditto, except mine charged just find, it was the regulator that was fubared, 18+v aint good for my car.. mm that smelt good.