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R33 No Start, Alternator?

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Testing with a 5W bulb in a test light won't tell you what's happening when you're trying to ram several hundred amps of cranking current through the starting curcuit. You need to unbolt the terminals of the earth lead and physically check / clean them. I've seen this problem before with poor earths. They run low current fine, but increase the current and they play up. The fact that it starts properly when you're using a different earth (and possibly positive terminal) hints that your problem lies with poor contact.

this is where i am leaning. i've been hooking the spare battery up under the bonnet. i'll try hooking it directly to the battery in the boot. when i have the key in and turned to on position everything works in the car except for windows. so maybe youre right, it will draw small amounts of power but not enough for everything. but once i turn the car on with spare battery, and unhook the spare battery (from under bonnet) the windows work fine. i dunno, doesnt really make sense to me. we'll see.

Perform all the tests i said. checking just the battery voltage will tell you next to nothing apart from if the battery has dropped a cell or more

Crank and check voltage (get another person to check it) and tell us what you get

A stuffed alternater will not stop the car from starting on a fresh battery

Has your stater been out recently?

i have no idea as to car history. bought it 7 days ago... ran fine for a week no issues whatsoever. there is a lot of aftermarket wiring running around this demon. with alarm, turbo timer, sound system... gauges... and a few other little bits, there is a lot of wires and fuses thrown in everywhere, i am not too sure where what goes to.

as for checking cranking voltage i would have, but there was nobody around to check for me this morning.

Check connections on starter mate ....

a starter problem just doesnt make sense though. the starter starts the car just fine when i have jumper cables hooked up to the positive post under the bonnet. i doubt its a starter issue. car starts fine when its getting power. if there were starter connection issues, then it shouldnt start regardless of whether i hook power up under bonnet or boot.

thanks for all the replies guys. i'll keep you informed on what i find when i get home this evening. if nothing, then its off to the shop tomorrow morning. between school and work, i dont have much spare time to muck around, as much as i'd like to.

89CAL Grand Master

89CAL

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I would check some voltages at both the battery terminals and the terminals in the engine bay,you may have a problem with the alternate charge getting to your battery and your battery voltage getting to the front of the car

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unfortunately i didnt have a second hand to help out with cranking the car while i check battery volts.

however, i did hook up the spare battery to the battery in the boot and try to jump that way. got nothing. but when i hook up to posts under the bonnet she fires up.

so i am betting on some kind of electrical short/problem between battery and alternator somewhere, and this problem is also affecting the ignition circuit.

i checked, tightened and cleaned my earth connections in the rear, as well as the ones under the bonnet (brushed them up with a wire brush, and reattached them) but everything seemed good to begin with. so the problem is electrical. i just have no idea where it might be.

89CAL Grand Master

89CAL

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Yeah i was leaning towards that. Best bet is to follow the cables (not sure if they run underneath the car or in the car) and check for shorts or breaks

Not real helpful but seems like your on the right track

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i'm still looking to find the bad connection. but i also decided to check alternator on the posts under the bonnet, before i only checked it on the battery in the boot.

it seems that under the bonnet my alternator is charging 15.2 volts... overcharging... but none of that is going back to battery, and nothing from the battery is getting to the front... so i continue to look for my short... but at least i dont necessarily need a new alternator. we'll see if its still overcharging once everything is fixed.

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SOLVED!!!!!!!!!!!!!!!!!!!!!

thanks for all the input and ideas from everyone.

ended up finding a bad connection under the bonnet. i didn't trace it all the way around to see where it went. just went as far as i had to. as this car has a lot of aftermarket wiring floating around, and i didnt want to bother trying to decipher it all, i'll do that in the future if i have to.

everything seems to be good. she fired right up when i repaired the earth wire, the earth itself was corroded, and the wire was rubbed through in one place. but that's what you find in a 17 year old car.

checked the charge at the battery in the boot, she is charging 14.1 volts... slightly less than my desired 14.2-4, but what're you going to do. i'll just write it off as a slight inaccuracy in my voltmeter.

cheers all

89CAL Grand Master

89CAL

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As long as its around 14V its fine. Mine charges at 14.0V sometimes and 14.5V at other times (Have the voltage displayed on my turbo timer)

Should be all good, glad to see you solved it. Thought it might be something simple like that after you said it worked fine when powered from the front. Amazing how something so small can have such a large effect :)

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