Electrical power loss problem

[Dntget2upset]

So I have a strange electrical fault i think is the alternator being faulty but not 100% sure.
I turn ignition on battery light works then goes off when I start the car can drive for a bit all fine then I start loosing electrical power clocks flicker power steering goes radio goes off headlights flicker. If I unolug the alternator two pin wire and sit on idle all is fine can run for about 30mins all electrical loads switched on idleing untill battery voltage starts to drop to 11v so I plug wire back in alternator starts charging and every so often drops to 0v measured from alternator main cable to battery earth. It's like the alternator is not only stopping charging it's sucking all the power from the car intermittently.

 

[Dntget2upset]

FIXED IT so before I replaced the alternator I thought I should check the load wires under the starter motor they wasn't snapped but was damaged so I cut them near the connector removed battery and followed wires back a bit to where they go over the power steering reservoir cut them and replaced with new wire and heatshrinked then looked back into the wire protection and plugged in drove car for around 5hours and didn't fault once

 

[R3k1355]

Alternator load wire is a common fault.

Also if you've got a PD130 the starter solenoid wire is another common one for snapping and causing problems.