[Shotimes] Crankshaft Position Sensor?

[(Test) Beckers, Shawn]

Thanks Mike!  I had no idea I could run the codes myself.  The 'engine off' test resulted in the following codes: 172, 211, 332, and 336.  I'm guessing that code 172 (rear O2 sensor running lean) may explain my fuel efficiency problem (although I would have guessed it was running rich) and code 211 confirms what you stated about the CPS.  I'm not really sure what codes 332 and 336 are trying to tell me.  Maybe someone could give me a hint on these.  I ran the 'engine on' test as well but didn't receive any codes at all.  I'm guessing I should have at least gotten a code 111 so I must have messed something up (even though I tried three times).  I'll probably try again to see if anything comes up.
 
Before replacing the CPS, I may take Erik Balser's advice and replace the CMP.  The part is cheap and it looks like something even I could do myself.
 
Thanks to everyone for their help.  I've learned a lot about my SHO today!  By the way, I'm located near St. Cloud MN so if anyone knows a good SHO mechanic in the area I'd appreciate the referral.