[bigfish95971]

Yes sound liek alt but could be a shorted batery too. But I think alt because when running alt should put out 14v. Pull alt and batteries and have them load and bench tested at a parts store. Do this after cleaning and checking all battery terminals to a shiny metal connection. A broken ground connection there could also do it.

 

[bigfish95971]

Sorry but how things were a month ago means nothing. But if that is the case you should start by pulling the alt and have it bench tested at the store. It is free.
Hosing it down should not have hurt anything.

 

[bigfish95971]

What was the voltage on the alt during the bench test? Maybe just bad battery terminal pr cable. maybe pcm ois bad and not regulating charge. There is also a batter temp sensor under the driver side battery, but I do not know its symptoms exactly.

 

[bigfish95971]

You can spend extra onaftermarkey alternators if you like, but not really necessary. The stock 136 amp is fine, I prefer the Bosch version if you can find one. It is better than the Nippon Denso versions and has less high AC issues. Avoid Napa nippin and Napa versions. Does your have small screw type connections or the plug on the small wires?