Is my mass air flow sensor bad?

I have a 2000 Chevy Impala with 3.8L v6. It is idling really rough. It was fine i took the exhaust off to repair a rotten section. I put it back on and when i started it it is just running like crap. If i unplug the mass air flow sensor it runs smooth but rpm's high, so does this mean the mass air flow sensor is bad?