Electrical problems and engine stalled

[Philthy]

This morning on the way to work my headunit and heater would cut out, then kick back in instantly. It happened probably 20-30 times in 5 mins before I just turned it off. It has happened twice before over the last few months (just once each time), so I earthed to headunit better (stopped using factory earth wire), but didn't have the heater on either time so I'm not sure if that cut out before or not.

Just before on the way home, everything had been working fine and the engine just stalled at the lights with no cough or anything, but the music was pretty loud. It started up again just fine right away. Plenty of fuel, demister on low.

Battery is an optima yellow top only 6 months or so old, haven't had any lights dimming with a fairly big stereo, and I have upgraded the battery and engine earths to 4awg. There is a bit of alternator whine in it that I can't seem to get rid of, but thats the only other electrical issue I have

Any clues would be helpful

[hako]

Check the big fat cable that connects to the back of the alternator and feeds power to the battery - it has a habit of breaking internally resulting in erratic power and/or engine cutout. You will need to remove the engine cover (4 nuts) to inspect....see if it moves plus visually you may see that it's been overheated.
Good Luck.

[Philthy]

It doesn't look burnt, and is still well attached, but upgrading it has been on the to-do list for a while so I'll get on that this weekend.

The mechanic at work said (without looking at it), that it could also be the main power wire off the battery so I'll check that out when I get some time in daylight as well