Sudden Dying

'87 CRX Si Battery light started to intermittently flash 3 days ago, headlights flickering, fluctuating voltage at batter, all the things that point, I thought, to alternator or voltage regulator. I replaced the alternator yesterday, test drove it and perfectly fine. Drove it to work today 72 miles one way, drove great. 2/3 of the way home this afternoon the radio cut out, the clock shut off and about 30 seconds later the car lost all power and died. About 20-30 minutes later while waiting on my wife to bring jumper cables and tools I tried to start it. Fired right up drove just fine for another 10-15 miles then same thing happened. There was no battery light flickering prior to either incident or anything else unusual. It almost seems like when it reaches normal operating temperature it cuts out. Is there a thermal coupling someplace or could it be a short in the cooling fan? Any thoughts appreciated since the little darling is currently sitting all alone along side the freeway.

You may have gotten a bad alternator, It's happened to me.

Also check your battery terminals. Corroded or loose terminals will cause similar symptoms.

If this doesn't solve the issue, check your fuses, relays and main fuses. If there's nothing funny there, then you get the fun job of tracking down an electrical short.