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Did I Get Hosed?

Have I been hosed? I have driven my 2004 Subaru Outback since August of 2011 and performed routine maintenance. I drove about 1000 miles the week before without any problems. When coming out of a bank on Monday, the car started great but would not stay running. If I kept it in park, and fed the gas, it would keep going, but then stall if I let up. If I shifted into gear, it would stall.

I called an indpendent mechanic I trust and when I described the symptoms and told him I had left my key with the electronic door opener on it at a stop earlier in the week…he suggested that an anti-theft function may have kicked in. I locked and opened both front doors, but that didn’t help.
Eventually I was towed to a Subaru dealer where I could get diagnosis. they told me if the anti-theft feature had kicked in, it would have started sooner.

In the end, I bought an after market alternator and I’m running fine.

But I have had alternators go bad before,andd it always involved the battery not charging. In my case, the car turned over and started successfully for 20 minutes. No dashboard lights came on. I would have thought maybe a clogged fuel line first?

In any case, would the symptoms I described be because of a failed alternator?

As a woman on the road alone, you get a little paranoid,. thanks for any thoughts

You only got hosed if you paid too much for the alternator. Obviously it worked.

The battery started your car, but if the alternator develops too much ripple in its output, say from a bad diode and it was not completely damped out by the battery, then that could have messed up the computers ability to control the fuel flow correctly.

+1 to Keith’s comments.

In modern cars with all their security devices, a loss of electrical power can cause all form of anomolies to happen. It seems the guy you called did the job right. And even if his cost was a bit on the high end, you still got your moneys worth.

This is complicated. Folks here make good points. But that is not how these DC circuits really work. The big issue is that the voltage regulator is built in to the alternator. All other possible issues aside if the car did not have enough volts the sensors and the computer cannot work. The level of voltage is controlled by the alternator. But only because cars now build this in to the part. It does not need to be there, thats just the way it is done.

Usually the alternator warning light will come on if it isn’t working. Or the dashboard charging guage would indicate the battery isn’t charging. Did you see anything like that? It’s possible though that a single diode went bad, which might prevent the warning light from coming on.

The symptoms you cite are indeed unusual for a bad alternator. But not impossible, especially with today’s cars with more intense electronics. Since it seems to be working now, maybe don’t look a gift horse in the mouth.