strange electrical issue with my 944

[nickbartleet]

I replaced the voltage regulator on my 944 as it was worn out and since then I've been getting this strange thing.. when I go to start the car it will regularly just cut all the power... Everything dies. I have to disconnect and reconnect the battery to get another go of starting it. As soon as the battery is disconnected and reconnected voltage is restored and I can start it. After a few attempts it invariably starts.

Anyone every heard of anything like this happening. The voltage regulator was a good quality one and it did fix the problem I was having with voltage fluctuation from the old worn out one.

[Kas750]

Possibly a faulty earth which may of damaged the reg initially also

[nickbartleet]

And now she won't start... no spark. DME seems to be fine as getting 12v pulse to the injectors and the coil on turnover. Fuel pump all good.. DME relay ruled out. When you turnover there is a discernable voltage drop on the cockpit voltmeter to 8v. Battery fully charged and brand new a few weeks ago.
Removed the new voltage regulator and there is uneven wear like the prongs are not riding smoothly on the rotating contacts inside the alternator.

I checked the resistance across positive and negative on the ignition coil and it was reading about 1ohm, not .6 as suggested elsewhere but feels like this could be a red herring.

Anyone had issues with replacing the voltage regulator as it was a real pain when I first installed it with having to reseat it in the alternator a number of times before the car would start.

[nickbartleet]

Thanks for this.. I just wonder if the alternator is a bit worn to take a new regulator. The regulator just doesn't seem to want to sit nicely on the two rotating contacts