Well actually, Code 32 is EGR circuit (fuel-injected models) and 45 is Oxygen sensor or circuit - rich exhaust. Most likely your EGR system is not operating properly and instead of recirculating the exhaust gases, they are being dumped causing the code 45, rich. If I had to guess, I'd say the most likely culprit is the EGR solenoid, is not sending signal or the EGR is stuck shut. Neither will cause running problems, you are just polluting more.
I'd check all the vacuum lines going to and from the EGR and EGR solenoid first.