Ok, my friend has a 95 Buick LeSabre with a 3.8 engine. He took the car to
some real shady shade tree mechanics for them to drop a different engine in
for him. These guys took the wiring harness off at the firewall when they
pulled the engine out, thye scraped the engine and wiring harness at the
local salvage yard before they got the other engine delivered. When the used
engine was delivered they noticed it didnt have a wiring harness so they went
and got a wiring harness for the car but it wasnt the correct one so they did
alot of splicing to get the connections to hook up to the engine. The car
would run but 2 problems:

1) Fans wouldnt come on so someone ran a jumper wire to a power source

2) Car was not charging.

He took it to a shop and the guy was stumped, now at this point I am not sure
if someone from there ran a power lead from the 12 volt power inside the car
to the alternator or what. It was spliced in the line. Supposedly it was
charging the system, but all I could tell was a major draw on the system and
my gauge and volt meter said 0 at the battery and my volt meter said 0 at the
terminal on the back of the alt that goes to the positive on the battery.

He brought the car out to me work on and I disconnected the wire that was
from the PCM. This alternator has 2 wires, one that goes into the wiring
harness and one that goes from the positive battery to the terminal on the
back. I replaced the battery, had the alternator tested and it checked good
but I put in a different alt to be sure. Still nothing, it was at 0 volts.
At this time I got the correct harness for it and put it on, the brought the
voltage up to 12 volts while running, but the lights were flashing like a
police car and the warning lights on the dash were flashing. I put in a new
alternator and that got the lights to stop flashing and the dash lights arent
flashing on and off and the volt light isnt coming on anymore. Volt readings
at the battery are 12.0 while running and 12.0 at the alternator. When I turn
the car off the volts jump up to 12.5 -12.6 and when I turn on the lights the
voltage drops to 12.0.

I have tried several different PCM's and they all offer the same voltage
readings as well. Something else that is weird is that I cant get the OBD II
diagnostic port to work. When I plug my scanner in, it has power there, but
it brings up a Link error code check connection.

This past week I have checked the battery and put a load on it, it tested
good. I took the alt off and had it checked at 2 different Autozones, I have
checked the battery connections and wiring. I have checked fuses and relays
as well. Checked the belt and it looks almost brand new. One thing I did
notice this week is that his AC compresser unit is bad and the pully while
running makes a major noise and watching the pulley it vibrates and shakes
for 3 seconds and then goes normal. Could this be enough of a drag to cause
the alt to not fully charge at the 13.5 volts it needs? When it does this
vibration, the volts stay steady and doesnt drop.

Also the cooling fans are still not working, could a cooling sensor cause a
drop in voltage? Also is this the sensor that is located under the
throttlebody that you need to take everything on the drivers side off to get
at?
I also noticed that the car doesnt shift like it should and he said it always
shifted good when it was running before, thats why I am wondering if its
somewhere in the PCM, but Ive had 4 different PCMS on the car.

Any help, ideas , thoughts , prayers, blessings, or suggestions would be
greatly appricated.