so after having starting issues and then a lean trouble code (actually two, one from eachof 2 banks) i replaced the fuel pressure regulator (a beast but not as bad as i thought) and then the fuel pump (which wasn't so bad either, with a trans jack). now the car runs just fine but is throwing a trouble code of running lean in the 2nd bank. any suggestions of where to start looking?

 

An exhaust leak prior to the O2 sensor would make the sensor read lean (too much O2 in the exhaust stream). That is where I would start looking.

 

went and had the codes checked again, small leak in evaporative system, so thinking i may have a vacuum leak after doing the FPR, making a funny rattling sound that comes and goes with engine speed

 

What was the actual code? P0442? This is not a leak anywhere on the intake side, but rather, somewhere in the EVAP system which controls evaporative emissions from the fuel system (tank). This is most commonly caused by a loose gas cap, but could be from a faulty o-ring seal on the gas cap or a leaking vent solenoid.