Weird Starting Issues

[bassboy3313]

Hey. Here is the story ...

Awhile back my 91 240 would only click when trying to start. I replaced the battery and still nothing. I took it to a shop and they said it was the starter and after they replaced the starter it was fine. a couple days after that the battery light slowly came on. it was fine for the 2 days i drove it with the light on until last night.

I started it and let it idle to warm up. when i came back outside to leave the car was not runnign anymore. i went to go start it again and the dash lights were dim and it clicked onced and then nothing. i figured, ok the alternator is bad since the new battery is now dead after 3 times driving it.

this morning i went out to see if it would start and it fired right up. i let it idle for awhile and everything was good. i drove it around the neighborhood for about 5 minutes. when i pulled back into the driveway, it immediately started bogging and then died. i tried to start it up again and it just clicked.

What could cause this? I am desperite since there are 3 people in the house with only 1 car now. if anyone can help I would greatly appreciate it. thanks.

[sx moneypit]

Sounds like you have got a bad diode in the alternator or the alternator is just worn out.The reason it started the next morning is because the battery built it self back up.

[bassboy3313]

i just went out there now to see if there were any loose or dirty conections, but nothing. i started it and it fired right up. the battery light is on tho. dont know if that has anything to do with it. its just weird how it works then it doesnt, then it does and so on and so forth.

[sx moneypit]

It seems like about every month or two i will get a customer with the same problem you are having.One day the alternator will work, the next day it wont.It is usually a diode going bad.

[bassboy3313]

so you are certain its a diode in the alternator then? is it possible to replace the diode itself in the alternator, or is the only solution a new alternator?

[sx moneypit]

Last time i put in a diode plate was in the 70s.It is cheaper and easier to replace the alternator.

[bassboy3313]

ok. thats what i read on a site about alternator diodes too. it says the battery light on the dash will light up very dim if one diode goes out and then get progressively brighter as more diodes go out. thats what happened with my battery light on my dash. i just thought the lights were faulty since my gas light is always on even tho i have a full tank and my e-brake light is on even tho it is disengaged. guess i was wrong about the battery light.

now the question is, is there a DIY on how to remove the alternator?

[sx moneypit]

There is an article in the 240sx tech pages,it is under engines and swaps.

[bassboy3313]

i found the tutorial on the nicoclub mechanic site. thanks tho. im gonna go ahead and replace the alternator then. cross your fingers thats the problem. lol.

[OutToWinPAHC]

You need a new alternator.

[sx moneypit]

Be sure and give your battery a good charge before you start the car. The alternator isnt meant to bring the battery back from the dead!

[bassboy3313]

i dont think it needs to be charged. its less then 3 weeks old. it started up fine this morning when dirving into the garage to do the alternator. i jsut got the new alternator and am installing it now.

[sx moneypit]

If it started the car then you should be ok. You just dont want to kill your new alternator.

[bassboy3313]

its a success. the battery light and the e-brake light on the dash went off now. the seat belt moves quicker than it did before. that seemed to be the problem. thanks for all the help everyone.

now to figure out the stuttering on acceleration and rpm fluctuation when revving to 2k and letting it drop it drops to 500 then raises back up to 1100 then back down to normal idle (700-800 or so).

[sx moneypit]

Glad to help!