Charging system problem
Hello, first post here, thanks in advance.
I have a 1992 325i with 114k miles.
A few weeks ago I drove cross-country, 2300 miles. 1500 miles in, my alternator died on me. At least that's what I was told. I was on the interstate, going 80 mph when suddenly my battery light came on. When I noticed that, I turned my radio, heater and fog lights off, also dimming my interior lights as much as possible. 45 mins later, I lost power steering, power brakes, headlights became flash lights and I pulled over. I tried my best to keep the engine running, which required me revving up to 5k RPM or so. When I let go of the gas, the engine stalled. Battery light, red check engine light and ABS lights turned on.
Had a new alternator put in. My old alternator, I believe, was a 90 amp. I had a 140 amp put in.
This Monday, I was driving at night when my red check engine light came on and my headlights began to fail me. I pulled over, turned off my lights and let the car idle. Check engine light went off. After a few mins I attempted to resume driving, but I believe the transmission was stuck in a high gear or something as there was barely any power. I turned off my engine in hopes of that little problem resolving it self. Battery was dead, car couldn't start. Waited 15 or so mins for the battery to catch its breath and started the car again. Drove home with no problems. Red check engine and ABS lights but no battery light.
The next morning I had it looked at and was told the new alternator was faulty. Had it replaced and installed, at absolutely no charge to me. Was told the old alternator was only giving out 11 amps. After the new one was installed, was told it is now giving out 13 amps and everything was as it should be now.
Last night...same thing again. Was on the freeway, going 60ish when my check engine light came on. Headlights started to dim and I could feel power steering starting to go. Exited freeway and parked in a parking lot. Turned off my headlights and left the car running for about 10 mins. 10 mins later I turned my headlights back on and continued driving. 15 mins later, my check engine light came on, headlights dimmed, lost power steering and the engine had absolutely no power behind it, but I was two blocks away from my destination, so I just went for it. Red check engine and ABS lights, no battery light. Like an idiot, I turned off my engine when I got there and was naturally unable to start it up again. Got a jump, made my way home, stopped for gas, needed jump again, went home.
When I got home, I left the engine running for a good 20 mins. When I turned it off, I started it back up no problem. This morning it started it fine, too.
Long post, I know. But this is the best I can do since I am not very car-savvy. Nor do I have the money to take it to some mechanic and be like "something's wrong, please find it" and later be charged with several hours of labor.
Hopefully with your help, I can somewhat isolate this problem. Even better, maybe it's something simple that I can fix...doubtful, but still.
I've had the battery tested at two different places and both say it's good.
Thank you very much.