, wI have been reading through past posts and soon realized I was in the right place! I have a 1989 Caprice Classic Brougham...a real gem! I am experimenting with getting readings through the ALDL using Winaldl (which is an awesome program-hats off to Jonas Bylund!) Anyway, the car runs fine until a load is put on the electrical system E.G.,lights, wipers, etc. and the voltage drops ALOT. Even stalled once with a heavy load on it.My question to you pros is.... Shouldn't the ECU give an error code if it is alternator? I thought it was a short somewhere in the lighting but I am almost certain of it being the alternator. Symptoms..random flickering of interior lights, drop in volts with headlights or brake light. Both turn signal indicators are lit when lights are on. Replaced all fuses and flashers Any suggestions would be very much appreciated! Still trying to decipher all the data from winaldl, will take playing with it I guess to understand what normal factory readings should be, which I won't get until voltage problem is fixed. During the night I looked outside and the blinker light was flashing and dome light flickered on and off randomly......I appropriately named the car "Christine"! Glad to be here!!!