electrical

[bacwy1]

ok guys i have a serious problem i think. my 85 went completly dead tonight. i know i might find my answears in the search but i dont have time since im stuck in a lot that is giving me untill the morning to move it. here is what happened, i was letting my engine warm up and all of a sudden the engine started sputtering. i reved it up at the throttle on the engine and it ran fine when i released the throttle it started to sputter again. i looked on the dash and the red light next to the battery was light up i ran the throttle on the engine again and it was running smooth and than it started sputtering and died. i tried to restart it and it was dead. my friend gave me a jump and it started right up but all of the cabin lights were dim and the radio had interference in it. when i turned the lights on the marker and rear lights came on but the head light wouldn't turn on. i went two blocks and the car died again. i think that it is the alternator or a fuse. the alt belt is fine i checked it and it is tight. any help is greatly appreciated so that i can try and fix it tomorrow before it gets towed.

[CJSREDPRA]

Very dead alternator.... Your trying to run off of a dead battery & the car is not really going anywhere, because there is not enough battery juice for the EFI system.

Find a spare fully charged battery. Pull out the dead one & swap it in. Hopefully it will be enough to get you home, or else plan on getting a tow. Change out your Alternator & Voltage Regulator.

[Chrisfrom1986]

voltage regulator? what and where is that. also, arent cars supposed to run off the alternator without haveing the battery attached? on my 82 as soon as you remove either battery cable, it dies.

[bracham]

Voltage regulator is on the alternator on the Supras. And yes, the engine will die when you remove the negative battery cable, but if the alt is good, it should keep running when you remove the positive cable. Put a volt meter on the battery posts and it should read 14.5 - 14.7 volts if the alt is good...at least when the engine is revving 1000 or better. I'm not exactly sure if it'll show that at idle. Less than 14.5 volts, your alt is on the way out...and less than 12 it's toast. I've had a couple alts that ran at mid 13's (volts) and kept the car going and battery charged for a long time...but had to leave it running for a bit after I'd boosted the stereo so the battery wouldn't be dead.

[Chrisfrom1986]

Voltage regulator is on the alternator on the Supras. And yes, the engine will die when you remove the negative battery cable, but if the alt is good, it should keep running when you remove the positive cable. Put a volt meter on the battery posts and it should read 14.5 - 14.7 volts if the alt is good...at least when the engine is revving 1000 or better. I'm not exactly sure if it'll show that at idle. Less than 14.5 volts, your alt is on the way out...and less than 12 it's toast. I've had a couple alts that ran at mid 13's (volts) and kept the car going and battery charged for a long time...but had to leave it running for a bit after I'd boosted the stereo so the battery wouldn't be dead.
i think my problem was that it idles at about 500 rpm. ill try it again later.

[bracham]

Shouldn't matter what it idles at, I don't think. The alt should charge enough, even at idle, to keep the engine running.

[Chrisfrom1986]

:x its new too... oh well, thanks to lifetime warranty ill just go get a brand new one :) but what bitch to change them :mad: