Random Electrical Power Loss in VYII V8 LS1

[calaiscruise]

I have been enduring an intermittent electrical fault in my 5.7L V8 VYII Calais that is getting worse.

I have ready many threads, but found none with my exact problem or solution.

I've never had any electrical issues until about 6 months ago, when I noticed a high pitched engine speed related "whistling" that appeared to come from the front passenger foot well speaker.. but if I turned the radio off, the whistling remained. It would occur intermittently then disappear, but only once the engine warmed up, and in stop start traffic.

It progressed to the radio sometimes powering off, then rebooting a few seconds later. Weeks later the engine stalled, but only as I was slowing down to a standstill, just before the car came to a complete stop. I could restart the engine without problem. Then for the first time ever it stalled as the car was moving at 50kmh, I took it straight to NRMA Motorserve who did a battery/charge/drain test and found no problems (???). Also asked a auto sparky mate, who suggested typical checks.

Knowing intermittent faults are the hardest to find, I began inspecting engine bay electrical leads, connectors, earthing point (front drivers guard under ABS module), battery clamps, for tightness, corrosion, and voltage drops and found no issues. When parked and running voltages are fine and the faults do NOT occur. Cleaned all connections, car ran fine for months.

Then it returned again, and I noticed the Climate Control fans seem to slow down when the radio whistle appears. I inspected the engine bay fuse terminal block, and cleaned up a mildly unclean (dusty) connection. Car ran fine again for weeks.

This week returned again, and stalled again in traffic. It's not a fuel flow failure as the instrument panel, radio display & aircon fans stop, before electrical power returns and I can always start the car immediately & drive away ????

I took to NRMA Motorserve did another battery/charge/cranks test and told me the battery is fine, excellent cranking amps, alternator fine and charging.

My logical is it must be an common electrical supply problem to the engine management, instruments, and radio, and probably a loose connector that but I'm dammed if I can find it.

Before I give me car to an auto electrician who will probably just start replacing every electrical component, has anyone had this exact problem and resolved it?

 

[Grandads’ Toy]

I have been enduring an intermittent electrical fault in my 5.7L V8 VYII Calais that is getting worse.

I have ready many threads, but found none with my exact problem or solution.

I've never had any electrical issues until about 6 months ago, when I noticed a high pitched engine speed related "whistling" that appeared to come from the front passenger foot well speaker.. but if I turned the radio off, the whistling remained. It would occur intermittently then disappear, but only once the engine warmed up, and in stop start traffic.

It progressed to the radio sometimes powering off, then rebooting a few seconds later. Weeks later the engine stalled, but only as I was slowing down to a standstill, just before the car came to a complete stop. I could restart the engine without problem. Then for the first time ever it stalled as the car was moving at 50kmh, I took it straight to NRMA Motorserve who did a battery/charge/drain test and found no problems (???). Also asked a auto sparky mate, who suggested typical checks.

Knowing intermittent faults are the hardest to find, I began inspecting engine bay electrical leads, connectors, earthing point (front drivers guard under ABS module), battery clamps, for tightness, corrosion, and voltage drops and found no issues. When parked and running voltages are fine and the faults do NOT occur. Cleaned all connections, car ran fine for months.

Then it returned again, and I noticed the Climate Control fans seem to slow down when the radio whistle appears. I inspected the engine bay fuse terminal block, and cleaned up a mildly unclean (dusty) connection. Car ran fine again for weeks.

This week returned again, and stalled again in traffic. It's not a fuel flow failure as the instrument panel, radio display & aircon fans stop, before electrical power returns and I can always start the car immediately & drive away ????

I took to NRMA Motorserve did another battery/charge/cranks test and told me the battery is fine, excellent cranking amps, alternator fine and charging.

My logical is it must be an common electrical supply problem to the engine management, instruments, and radio, and probably a loose connector that but I'm dammed if I can find it.

Before I give me car to an auto electrician who will probably just start replacing every electrical component, has anyone had this exact problem and resolved it?

I don’t have a solution but my new toy has done the same thing today & prev statesman had lost all power on the highway once. Did you ever get to resolve the problem?

 

[BlackVXGTS]

Suggest you get your car scanned for error codes using a proper Tech2 (or equivalent) scan tool. Not all scan tools display history error codes. Since your problems are intermittent, the error codes may still be there in error code history.