Alternator Question?

[Lt4-turbo]

My Battery on my 86 GN is not holding a charge.I Charge the Battery to full charge and it lasts about 2 days before it is dead. I took the alternator in to have it checked at auto zone and o'reily's and they both say the alternator is good and running about 14 amps. I had the almost new battery tested and it tested out fine. I put the fully charged battery back on the car and let it run and checked it with a meter and it showed 11 amps and would go down to 9 amps. If I gave it gas it would go back to 10-11 amps. If I pull the positive cable off while the car is running the car dies immediately.
What should I believe auto zone and Oreily's or the reading I am getting from the meter while the car is running? An Alternator (120 amp) from Oreily's with a lifetime warranty is $100 is this about right or is this too high? Thanks, Jon

 

[85TurboTtype]

Good Price

That is a good price for a 120 amp...for sure... Sounds like a voltage regulator in the alternator is going... If the car dies when you disconnect the battery, then the alternator is usually at fault!! You may want to check your connections first.. Make sure that the plug in the back of the alternator is tight, along with the wire that comes off the back and runs down the side of the engine and goes over to the battery. Check all of those wires and conncetions.. Also start the car and check the reading comming off the back of the alternator.. should be like 12.42 or so.

Matt

 

[Lt4-turbo]

Matt, I did check all the connections and they were tight. It read about 10 amps comming off the back of the alternator.
So you think it is most likely the alternator? I was certain it was but am confused why the auto zone and Oreily's machine both read like it was good. Thanks, Jon

 

[Turbo Brian]

Are you confusing volts with amps?

Caspers makes a field fix harness that bypasses the factory wiring to allow the alternator to charge properly. If your alternator charges fine on the bench, you may have a wiring problem that the field fix harness can solve.

 

[1stTurboGN]

even though autozones test shows the alternator is charging (which it may be) if something is wrong with the internal regulator, it will drain the battery when the car is off because, to put it basically, the alt. doesnt get disconnected from the battery via the regulator and it tries to act like an electric motor and drains the battery.

 

[85TurboTtype]

All signs point twords ALTERNATOR!!!

I would say that all signs point twords your alternator being bad!!! If your reading was volts not amps at the rear of the alternator then I would give it a 99% alternator bad.

P.S.- 1stTurboGN...nice quote from Under Seige 2!!

 

[Lt4-turbo]

Yes, I ment volts not amps. I think I will go ahead and buy the new alternator. The old one is the original and has 89,000 miles so If it is not bad it will be soon anyway. Thanks for all the posts. Jon

 

[Bent6]

When you turn on the ignition, does your VOLT light come on before you start the engine? If not, check the bulb. Due to a very poor design by the engineers, if the bulb burns out or is loose, the regulator will not be activated. This will cause the exact symptoms you are describing. I have had this happen before on more than one car. Caspers electronics makes a field-fix harness that will prevent this problem by bypassing the idiot light to the regulator. Check your voltage with either a voltmeter at the battery or using a scan tool. You should be seeing around 13.5 - 14.0 volts at idle if the charging system is working correctly. You could have a fresh battery and working alternator, but the voltage would steadily drop as the battery is drained due to a non-functioning charging system. Your car dies when you unhook the positive cable because you are taking power away from the ECM, fuel pumps, injectors, etc. That trick doesn't work on modern day cars.

 

[Lt4-turbo]

I checked the bulb and it was fine. I put it in the fasten seat belt sockett and it worked fine. So that shouldn't be the problem. Thanks for that info. Jon

 

[Bent6]

When you turn on the ignition, does your VOLT light come on before you start the engine? If the bulb is good but doesn't come on when you turn the key to ON, you have a wiring problem. If it doesn't come on, try wiggling it around in the socket. I really don't think your alternator is your problem. The field-fix harness from Caspers would more than likely cure this problem. I assume you have checked all fuses under the dash. Hope this helps

 

[Lt4-turbo]

Bent6,
no the light doesn't come on when I turn on the ignition. The only light that comes on is the fasten seat belt light.
Do you remember how expensive the field-fix harness is and how hard is it to install? Sounds like that may be the problem.

 

[turbo2nr]

I would not reccomend any other alt, other than a 130amp GM unit, rebuilt or new, it has to be the correct alt. My car will drain batt also in 2 days. I have been running around in circles trying to find the culprit. I will now turn to the alt.

Scott

 

[turbo2nr]

If I take my belt off of the alt., will It spin by itself if there is a problem? Someone said the alt. may be acting like a motor sometimes when they go bad?

 

[Lt4-turbo]

I went to Caspers electronics site but I couldn't find the fieldifix harness. I don't know what to do. I was going to go get a new alt. but I don't want to replace it if it is not going to fix it and it sounds like it could be the harness problem. Thanks!

 

[85TurboTtype]

Suggestion....

You could purchase the new one. Put it in the car to see what it does/ how it acts.... Make sure to not touch it with dirty hands so that you can take it back if it doesnt fix your problem... It's only 3-4 bolts, so won't take much of your time!!

Matt

P.S.- Just tell em it's the wrong one....Call a different store location and ask them if alternators are returnable if they were purchased and not needed... Just called Autozone right NOW and they said that you could!!!

 

[85TurboTtype]

Fieldfix Harness....

Here you go Lt4-Turbo....

http://www.casperselectronics.com/M...creen=PROD&Product_Code=102032&Category_Code=

 

[Bent6]

Don't waste your time or money on the alternator. If you're not getting a VOLT light @ ignition on and you know the bulb is good, you have found your problem. I see someone gave a link to the field fix harness from Caspers. It's not expensive & a heck of a lot cheaper that an alternator. It is a good idea to install on any car whether you are having problems or not. I had the bulb problem happen on my wife's T-Type. I don't pay attention to the idiot lights before starting. Was cruising down the road about 30miles from home when the car started sputtering - saw the voltage was down to 8 volts. To make a long story short, I was on the side of the road on a Sunday afternoon with my pregnant wife! Had to call my brother in law to bring me a couple of batteries to get it home - naturally I thought "alternator" just like you! The field-fix harness will prevent this from happening. Good Luck

 

[Lt4-turbo]

Bent6,
Thanks for the information. I went to the Caspers link but I could not find the field-fix harness. I guess I will give them a call tomorrow. Was the harness very hard to put on? I love this site turbo regal owners are the best. I guess that is part of the reason I have had three of these cars. Thanks, Jon

 

[85TurboTtype]

Fieldfix Harness

Jon,

The link I posted takes you right to the fieldfix harness.....

Matt

 

[Lt4-turbo]

Matt,
Thanks for sending the link. I had tried to go to the link when you first posted it but my computer was not working right and It wouldn't work. My son defraged the computer tonight and I just clicked on it and it worked perfect. I am glad my 15 year old son is a computer wiz. Thanks again, Jon.