In January, I had the alternator replaced on my 2004 Focus after it died in the middle of the street. It’s been fine since then, but yesterday I was driving it and it suddenly seemed to lose power - the dashboard battery light came on, there was the dinging noise that indicates that a seatbelt is unbuckled or the headlights have been left on when you open the door, and the fuel needle dropped to empty (even though the tank was 3/4 full.) Then everything kicked back on. Then it happened again. This cycle repeated three or four times. I parked the car, restarted it, and after that it was okay. BUT - I have two long trips coming up, to remote areas of the Rockies, and I want to make sure it’s okay before setting off on these journeys.
It seemed like the alternator was bad, or maybe there was a loose connection, but I took it to the mechanic and he couldn’t detect anything wrong. The alternator is under warranty, so he’s suggesting that I just replace it, but also wants to run “other tests” to see what’s going on.
Of possible relevance: it’s been pretty cold out here for the past week (-5 F), I don’t drive the car that much, and it was the first time I’d started it in several days. The heat and radio were both on when I started it. I left it running in neutral while I scraped off the windows, which I usually don’t do. Generally I scrape off the windows first, then get in, start, and just drive. Sometimes it’s sluggish in the cold when I do this, but usually it’s fine.
Has anyone else had similar issues? Is it possible that this was just the cold? I’m wary of getting into a situation where the mechanic starts finding a bunch of stuff wrong with it that isn’t actually wrong.