Alternator problem... car dies?!

[F22-GURU]

hmm thats odd a spike on the ecu your not bosoted bro so stop worrying its as simple as turning your car off and on everyday . I hope you dont leave your car on everyday do you will it spike if you turn the key off while its in the ignition no. This checking of the altenator can tell if the altenator is good when the car cuts off if its bad its cuts off simple as starting yoru car and shutting it off everyday. Another sign of a bad altenator will lead to the draining of the battery because its not charging as someone mentioned in this previous post i forgot to mention. They work hand and hand. tallyho mynigg

Wow, you guy's have got no idea how the electrical system actually works do you. Man, they shouldn't let you loose under the bonnet!!
Where do you think the ECU and Ignition Coil get's its power from. If you take away the power source the engine dies, it's basic commonsense, it's just like turning your ignition off.
How from that can you tell it's just "the alternator", by disconnecting the Main Power source? What about the loss of power to all the relays & fuses. Have a look at how many wires go to the Alternator. So if the alternator belt is removed, you are telling me, that the engine will not run?

[RandomGuy]

well if the car isnt getting power from the battery and is still on... odds are its the alternator providing that power? by process of elimination... I am just saying thats how i've always diagnosed... Anyhow technique-arguing aside... I will put a multimeter up to the alt tomorow while its running to see if its putting out anything. Anyone know what numbers should be like?

[bruno8747]

Do like what I did when I had that problem. HIT it. I might sound crude but It works. Take a piece of wood and hit the alternator. It might make it work it might not but it works most of the time.

[dubdealer]

This might sound stupid but I had a very similar thing happen to my car. The culprit, a bad ground wire to the chassis from the battery. I know it sounds stupid, but might be something else for you to check out. I just needed to tighten it up at the chassis.

[RandomGuy]

Do like what I did when I had that problem. HIT it. I might sound crude but It works. Take a piece of wood and hit the alternator. It might make it work it might not but it works most of the time.

ur not funny

[F22-GURU]

well if the car isnt getting power from the battery and is still on... odds are its the alternator providing that power? by process of elimination... I am just saying thats how i've always diagnosed... Anyhow technique-arguing aside... I will put a multimeter up to the alt tomorow while its running to see if its putting out anything. Anyone know what numbers should be like?

so i figured, the battery isnt holding charge.. just charge it up overnight... pop it in... start it up... its perfect... i turn on the headlights, the car dies... so i figure its the alternator. I get an alternator from S & W salvage... under 50k miles on it tested above charts... good alternator 35 bux not bad?... Pop it in... put in a new alternator belt while at it. Charged battery.. car started up fine.. i removed the + terminal from battery, car dies... I dont know WTF it could be.?

In your original post you said when you disconnected the Pos Battery lead the Engine died?
The alternator is there to keep the battery charged as well as supply power to the Ignition Sources, but the engine will still run for a period of time with out the alternator connected.
Anyway, you should have a reading between 13.5 & 14.4 Volts while the engine is running at or above 1500 rpm. If it still reads around 12.5 Volts or less then the Voltage Regulator is at fault. Check to see if the Battery Light on the dash is glowing. If it's glowing bright it would be the Volt Reg. If the light is very dim then the Exciter Diode could be shot.
On the sparking alternator issue. No Metal, nuts or foreign objects fell into the back of the alternator did it??

[bruno8747]

ur not funny

I am not telling you to hit it until it falls off, I am just saying hit it a little and see if that changes anything. I did do that to my alternator when it started giving trouble and you know what it worked long enough for me to get another one. I am just trying to help but this is your problem not mines so its your choice on the solution.

[F22-GURU]

hrm thats odd... it seems almost like routine to check the alternator that way. Remove the + terminal while the car is on and if it dies it has to do with that. I've done this to troubleshoot in other cars without problems... Thanks for the help but the battery i bought in replacement was exactly the same model, same shape, same everything. Also when u buy a battery from a place like advanced auto or so.. the positive terminal is always insulated with some sort of covering.

Open up your HAYNES "HONDA ACCORD 1990 thru 1993 - All Models" Workshop Manual and go to Chapter 0 Page 17 - Second Column - THE BATTERY and read the first line.

Then Go To Chapter 5 Page 2 - 1. General Information - Part (C) and read that.

Turn to Chapter 5 Page 6 No 11 - Charging System Check. 1st line.
Then read the whole section.

I REST MY CASE!! Your Honour.

BTW: You should also check the EFI MAIN RELAY. You've probably fuck it as well.

[F22-GURU]

So have you figured out that you have blown The Rectifiers in the Alternator yet. That's what happens when you disconnect Battery Terminals while the engine is running. It the time it takes to lift the terminal off half an inch the rectifiers will be blown. About 2 Milliseconds.

Out of Interest, TysCb7, RandomGuy & H22Sparkle how often do you go through alternators using this method?
Pretty expensive Trial & Error excersize, hey

BTW: That's what be causing all the Sparks & Smoke!!

The silence is deafening!!

**EDIT**

BTW: This is not just my opinion, this can also be backed up by any Reputable Auto Electrician.

[h22sparkle]

[F22-GURU]

Well I invite you prove me wrong??

[TysCb7]

So have you figured out that you have blown The Rectifiers in the Alternator yet. That's what happens when you disconnect Battery Terminals while the engine is running. It the time it takes to lift the terminal off half an inch the rectifiers will be blown. About 2 Milliseconds.

Out of Interest, TysCb7, RandomGuy & H22Sparkle how often do you go through alternators using this method?
Pretty expensive Trial & Error excersize, hey

BTW: That's what be causing all the Sparks & Smoke!!

The silence is deafening!!

**EDIT**

BTW: This is not just my opinion, this can also be backed up by any Reputable Auto Electrician.

F22 Guru, what do you think happens in the event that the battery fails while driving? The alternator rectifier blows?! Disconnecting the battery terminals will NOT do anything to the alternator, I've done it many times to test it and never once has anthing happened.

[F22-GURU]

F22 Guru, what do you think happens in the event that the battery fails while driving? The alternator rectifier blows?! Disconnecting the battery terminals will NOT do anything to the alternator, I've done it many times to test it and never once has anthing happened.

Sorry I forgot, you are an Automotive Expert!!
Who cares if I've been a Professional Mechanic for 26 years, you must be right because you said so.

[accord91lx]

Wow, you guy's have got no idea how the electrical system actually works do you. Man, they shouldn't let you loose under the bonnet!!
Where do you think the ECU and Ignition Coil get's its power from. If you take away the power source the engine dies, it's basic commonsense, it's just like turning your ignition off.
How from that can you tell it's just "the alternator", by disconnecting the Main Power source? What about the loss of power to all the relays & fuses. Have a look at how many wires go to the Alternator. So if the alternator belt is removed, you are telling me, that the engine will not run?

Dude you're a tool. STFU on subjects that you know nothing about. I've driven across town WITHOUT the battery in the car! Not the best for it, But can be done in an emergency situation. I've seen you post in multiple posts with mis-information. Please stop.

To OP: If you've checked all fuses, replaced ALT, on thing to consider is the Harmonic Balancer (Crank pulley). I had this issue on my Gray car, Turned out the rubber from the harmonic balancer had seperated from the outer portion of the crank pulley and was causing the outer portion of the pulley to slip and not spin with the crank. I found this issue on accident. Definatly check that, as it could be your problem. I was able to wiggle the outer "ring". If you can move the outer ring of the crank pulley, it needs replaced.

[accord91lx]

Sorry I forgot, you are an Automotive Expert!!
Who cares if I've been a Professional Mechanic for 26 years, you must be right because you said so.

I suspect you've spent maybe 1/8th of that actually working on a car, and the majority of the time repeating what you've read across the internet...thats about the only way you could have this much misinformation.