I have a 89 crx dx with a b18a1 and the car was running just fine tell yesterday. The battery was dead so i jumped it and it started. I noticed my tachometer wasn't working so i gave it a little rev and the car wanted to die. What could it be?
Thanks

 

99% sure your alternator is done

 

With the car running, diconnect the positive battery cable from the battery. This will make the car pull power from the alternator. If your car dies immediately, then your alternator wasn't providing power and you need a new one.

or just put a voltmeter on the alternator while its running. Should be no less than 12V with the lights off, 14.1V with the lights on.