HI GUYS.

I hope you can help me with this. My car has originally an 12SI alternator, but I started having measures in the voltmeter about 17V. First I changed the regulator; it works ok a few days, so, after that the voltmeter begins to read below 13V, so far.
A few days ago I replaced the 12SI for a 130CS 100amp alternator, but the problems stills.

When I turn on the lights, a/c and rear def, voltmeter needle wanders 8 and 13 volts. Any idea of the palce of the problem?.
Thanks.

 

when you load the system you should see a drop in output. does the output increase with an increase in RPMs? it should. you don't want to see it around 17 because it's full fielding in that range and will burn out the alt.

 

Jose,

Welcome to ThirdGen.org!

I'd suggest checking connections. The likelihood of two regulators being bad is remote. Start with the engine grounds and chassis grounds at the firewall. Obviously, both battery cables would be suspects, and instrument cluster connections are also questionable. Have you verified the voltage reading with a separate, handheld voltmeter? That might reveal a lot.