Voltage regulator wiring dilemma

[greentrees]

Had to jump my car the other day but prior to that the lights would brighten as I give the car gas. I'm goin to try and replace the VR before replacing the whole ALT.

The problem is that the orig VR has a wire spliced, it's a white/red wire from the middle column of the harness. Is this a common thing to do and do I have to splice the wire for the new VR. BTW looks like the wiring on the car has been fiddled with quite a bit. I really want to go with the MSA ALT upgrade but will the VR adapter still be a PNP set up because of this wire splice and how can I fix it? Here's a couple pics to better illustrate...

the circles are where the spliced wire connects on the VR. PLease help this hopeless newb...:stupid:

[Zed Head]

Do you mean "cut" instead of "spliced"? Spliced means connected to another wire, generally. It looks like your white with red stripe wire has just been cut, but not connected to anything.

The VR just prevents over-voltage. The alternator supplies the voltage. If your lights are dim and get to normal brightness, that implies a weak alternator. If the lights are fine but get very bright when revving, you might have a bad VR. The best way to tell is with a volt meter while the engine is running.

[greentrees]

Well it is cut from the harness but the wire "from" the VR is connected to something else on the car (can't really tell from the pic), my guess is battery but I cant follow the wire very far as it is shrink wrapped with a bundle of other wires that seem to lead towards the battery. Can you tell, by looking at the connecting points on the VR, what the wire's purpose was originally? Thnx Zed for all your feedback.

[Zs-ondabrain]

Not really sure of the issue, if the VR is going to be pulled. However, if the engine harness before the plug is cut into, then I would do whatever it takes to back trace whatever it is going to. The POS (Previos Owner Syndrome) is an issue that most of us have had to deal with, at one point or another.

The 2 wires on the plug on the alternator can easily be found on the VR plug. The B/W?? is tapped by the condensor, next to the VR. That can stay there and left bolted to teh fender. The w/b and b/w deal with the ignition?? and that's what the diode in the plug (ZXP) is for, to keep the dreaded "Run-on" from happening. I'm refering to the issue that some owners face when doing the swap. It can cause the car to start but NOT shut off.

So trace the Tapped wire and see if it is of any importance to the new aloternator or ZXP (adaptor plug)

Dave

[Zs-ondabrain]

I just PM'd you. Now that I see the picture again, same rules apply. Once the VR is pulled and the stock wiring is ok on the engine harness side, I don't see an issue with doing the ZX alt swap using the ZX adaptor plug.

Dave