I have an occasional loss of power problem in my Focus. Once in a while, (every few days to weeks) the car acts like it has a dead battery. It has no power before start. It only lasts for about 1 to 2 minutes and comes back without doing anything to the car. I know the power is back when the dome light comes back on.
Today the same problem happened for the first time while it was running. it was just for an instant, but it happened as the car was slowing to go through a turn. When the power went off, the engine quit and no power to the dash lights or guages. Just prior to the power outage the guages went crazy and fluctuated up and down. They smoothed out when I sped up.
I know it is an electrical problem but I’ve never encountered anything like this before. Can anyone give me a place to start looking?
Start by simply making sure that your battery cables are very clean and very tight. You can buy a simple little wire brush cleaner for this at an auto parts store. Also follow your cables and find/clean/tighten any ground connections you can. Also have the battery and charging system tested - lots of auto parts places do this for free.
I checked them and the connections and cables don’t show any corrosion and they are tight. The battery and alternator both tested good and I even checked the engine ground.
Finally fixed the problem 2 weeks ago. The Alternator went out and took the battery with it. I don’t know why it took so long, but the alternator voltage regulator diode went bad and burned out the battery. both replaced and all is well again.