car keeps dying overnight
 

recently got an fc..
but when i park it for an hour or more it needs a jump start..
i had the car on and disconnected the batter which would mean its not the alternator riight? does that mean its the battery?

You probably should have posted this in this section -> 2nd Generation Specific (1986-1992)

We're going to need more information about your car. You may have something wired up incorrectly. (Car stereo, amp, turbo timer, etc...)

Charge your battery before doing this.

Remove the negative battery terminal, set a multimeter to AMP current (mA), one prong to the negative car terminal, one prong to the negative battery terminal, BE SURE ALL ELECTRICAL LOADS ARE OFF, now see if the multimeter is reading very very little current (mA) or zero... If it is displaying more than it should be, remove the 60A BTN fuse from the engine fuse box (so that you can open the door of the car without the lights coming on), go into the car and start pulling fuses from the fuse panel by your feet, one at a time. If that fuse doesn't get the multimeter to display zero, then put it back in and try another fuse. You can also try pulling other things... The way I found my drain, was by unplugging my turbo timer. The multimeter then displayed zero, and that's how I knew that was the problem.

post in the correct forum
this issue is common on FC's that have had the alternator changed for another from the wrong model FC
ie , s4 alt is wired differently to a s5 alt , and you cant just bodge the plug and make it go , you have to rewire it
this same problem comes up ( in the correct sub forum ) several times a month, search