P0194 error code
 

Good afternoon,
My wife has a 2004 Volvo v70 non turbo. The check engine light came on last week and the car started hesistating. I put the OBD on it and it came up with p0192 Fuel rail. The CEL reset and was fine for a few days then yesterday it came back on and today the car wouldnt start. She got it running then home. Should I replace the Fuel Rail sensor and hope thats the problem? The part is $170 but looks easy to replace. I just dont want to start changing out parts and not fix it. Thanks!!!!!!