E30 325 won't stay on

[Dubiousbtl@xxxxxxx]

Hello,

My  E30 325e won't stay running for more than a few minutes. I can start it 
up and it will idle fine for a little bit, but after not long, the idle lopes 
and drops down way low, then shaking and dead. On my way home, I felt like I 
was losing power, but I had to rev it up and stay in 3rd to keep going.  My 
headlights also dimmed severley and when I went to try high beams, I didn't 
have any light.  The battery is 2 days old, and I just replaced the 
alternator (with a used, tested one).  I can turn the key in "on" and with 
the car off, the headlights, both sets, are fine.

Thanks,
Cam
87 325

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