well today my CEL came on and i pulled off those 2 codes. (P0138-P0320)
the thing is i just got a brand new CPS like less then 1000 miles ago!
and as for the O2 sensor code, my muffler is just kinda thrown on there........ so maybe if i seal it up it'll be ok? and would it cause my gas mileage to decrease?

 

The P0138 is for your "downstream" (after cat) sensor. You MUST verify that all wiring and the connector for that sensor is perfect before looking elsewhere! Another possibility but more of a longshot is high fuel pressure (check with a gauge).

As for the P0320, it could be a flaky new crank sensor or it could also be involved with the camshaft position sensor, located inside your distributor. Where did you get your crank sensor? No lack of threads on folks having trouble with certain (not all) aftermarket crank sensors.

 

yea im going outside now to check the O2 wiring and all and seal up my exhaust.

and yes i got it from advance auto parts and its a BWD i believe....... i have a scanner and ill try to reset them and see if they were just a blip before i go swapping stuff out and all