I just learned of this site and I'm hoping someone here can help. I'm helping someone that inherited a 1981 ZX but I'm not familiar with the car so I'm learning right along. There's buzzing sound that's coming from what appears to be the rear that stops when the engine is shut off. Could this possibly be the fuel pump? Is this a sign of it failing?

Thanks

 

Hello! Welcome, the pumps are fairly loud, and you can hear it buzzing in the back. The more wear they have, or restrictions on suction side, which could be from rust in the tank, they will get louder and louder. It should almost be a nice steady humm, not a obnoxiously loud wine.
Cheers.