gtp running rough and gutless

My gtp has been running terrible and getting worse. I scanned it and got 3 codes. 0171 system too lean bank 1 0420 catalyst efficiency below threshold bank 1 0453 evap emission control system pressure sensor high. I had a mass air flow code before but i changed it out. I f you have any ideas i would really appreciate it.

What year is your GTP. If it's an 01-02, there is a known issue with the catalytic converters plugging the exhaust. GM actually extended the warranty on these for that reason.

Hey......miner327......Hibbing I see. Soon to be neighbors in July. I'm moving to Pengilly after i retire from the Air Force.

Lefty

'93 Grand Prix "Special Edition" 160K
'05 Grand Prix 63K

It is a 98. I had the catalytic converter replaced not too long ago. But I don't think it was plugged. It doesn't backfire it misses like it is starving for gas. I took the belt off for the supercharger and it doesn't miss as much but it still misses pretty bad.

I would check fuel pressure next.

i forgot i also checked the fuel pressure and it was ok. Could it be a plugged injector?