1995 Infiniti G20 4 cyl Two Wheel Drive Automatic 137K miles
I sometimes(1 in 10 drives) loose all electrical power (power steering and brakes, the clock, dome lights, everything). This happens most frequently when I'm coming to a stop or slowing down. The engine obviously dies too. The power will usually come back when I fidget w/ the battery terminals and I can start the car again. Sometimes I need only touch a terminal w/ my finger and power will come back. Rainy and cold weather make the problem appear more often. The problem doesn't seem to happen when I'm going faster than 25mph or so.
I have replaced the battery and thoroughly cleaned and tightened the terminals and the problem continues to resurface. When power is working as it should, I have tried flexing the battery cables very hard and have not been able to repeat the problem. I have also tested the battery w/ a voltmeter when the car is dead and the battery reads 12.8v. Infact, touching the voltmeter to one of the terminals seemed to return power to the car.
This is perhaps most bizarre. On a particular rainy day, electricity died several times. Although it may have been coincidence, I was twice able to get power to return the moment I slammed my hands against the steering wheel in frustration.
Replace the battery cables. 13 years of exposure to the elements will cause a cable to begin to fail. If you do a voltage drop test on the cables I bet you will find that the test will be out of spec. Make sure you replace the positive and negitive cables together.