have this problem thought had it solved overcharging but now it will output between 13 plus to 14 plus then few miles of driving engine sound like its coming under load light will double output , put multi meter on batter terminals out put will bounce from 17 plus volts into upper thirties the engine comes out of under load sounding and voltage will go back to normal output .Have search the forum but have seen nothing like this any suggestions would be great have put 3 new alternators 2 scans checked wiring 1994 cutlass v6 3100 when engine sounds like it coming under load head light will double there output all light will come on airbag,service engine abs, they tested my battery at 2 diffrent shops under load test said it was ok but do you think that may be false shows about 12.58 with car not running ,what would
fuseable links look like i see 4 wires on starter with large 12 volt feed the 4 are red im thinking 2 are for ign switch mybe other 2 for control module I don`t know look there spliced together with 1 inch rubber cover is that a fuselink and how would i test it . sorry for posting somthing almost same as last post how can i remove old posts

Yes I think I mentioned the fusible links before in your other thread.
They are the 4-5 large plastic things on the wires by the starter, if one is blown or corroded it'll cause some voltage spiking !!

Testing them for continuety from end to end, and for power/voltage at the ends .

Hope that helps & Good Hunting

have your alternator checked. If the governer (Voltage regulator) is whacked it will spike it... Just my 2 cents.

thanks for the input chakubanga and Welcome to AF!
... if you read the first post, he has installed 3 new alternators, not the problem IMO. :2cents:

thanks for the input chakubanga and Welcome to AF!
... if you read the first post, he has installed 3 new alternators, not the problem IMO. :2cents:

My Bad. I thought he just used 3 alternator to check and scan. I only see it as a source and consumer. In this case Alternator, battery and then the consumers. If the source is what generates electricity, spike will only come if that source is whacked.

Second guess maybe, and this is only if cables have been changed. To check the gauge of those cables.

Third to make sure resistors are original, since ohm law may dictate a different theory. Not to be insulting anyone this is the Ohms factor
To calculate the circuit voltage...
The formula is V = I x R Example: 2amps with 25 resistor will equal 50V.

Maybe go back with Fluke and check the resistors on the cable and then with ignition on and running do the rest of math....

Still trying.

Thats ok.

I just dont see it being something that complicated.
A corroded or damaged wire or circuit, if the alternators were good and new shouldnt be a problem.

I think I also discussed this before with brock02 in another thread.

Thats ok.

I just dont see it being something that complicated.
A corroded or damaged wire or circuit, if the alternators were good and new shouldnt be a problem.

I think I also discussed this before with brock02 in another thread.

This is the easiest Test. All you need is multimeter and know your cables, plug your meter and it gives you the reading..

Anyways where is the original poster? He hasnt posted or check the follow up of his own thread.. Until then...

Good Luck.