Nissan Repair: Altima smog check fail, rich fuel mixture, smog station

Question
My 2003 Altima 2.5SE just failed a smog check showing very high levels of CO. 1.48 at 791 RPM and 1.32 at 2466 RPM. It is running great. My engine code reader shows no trouble codes. Online searches seem to point to a rich fuel mixture possibly related to EGR problems but no solutions are posted. Can you help?

Answer
Jim,

First, I would change the sparkplugs.  Second, the air filter.  Third, I would get a tank of premium and add a fuel additive like Lucas fuel treatment.  Your choice on the fuel treatment.  Now, I would change the oil.  Now, drive the car on the freeway, with the air conditioner on and run the car for thirty minutes before pulling into the SMOG station.  You should pass.  Email me if you need more.