P CODES (POWERTRAIN) P0400 - P0499 P0420

Cat Code Keeps Popping Up, I Have Replaced The Spark Plugs, Map Sensor, Air Filter, And O2 Sensors. Codes Keep Popping Up, But I Don’...

Engine Light Went On. Engine Not Missing. Uses One Quart Of Oil Every 2,500 Miles. Reader Showed Load 48.6%, Btc 199 Degrees F, Shift Bi -...

I Got The Code Awhile Back And Replaced My Catalytic Converter The Manifold One And The Code Came Back Couple Hundred Miles. I Have Checked...

I Had One Of The Camry's That Had The Oil Consumption Problem To The Point Where It Burned A Quart Of Oil In Under Two Hundred Miles....

This Code Keeps Coming Up And We Are Running Out Of Ideas How To Fix It. Convertor Is Less Than A Year Old And Seems To Be Okay. O2 Sensor...

I Recently Replaced The Radiator, Hoses, Thermostat, Plugs, And Wires. Car Was Ran A Few Times With Misfiring Plug, Now I Get The Cel...

Hey, Guys I Replaced The Trans. Bearings, Took Car For A Ride, The Engine Light Came On, I Pulled The Code P0420 Cat. Eff. Below Threshold...

Hi, I Have Been Battling This P0420 Code On My Car (gt Model) For A While Now And Was Hoping Someone Would Have Some More Insight On The...

What Causes This Code And How To Diagnosis The Causes?

The Catalytic Converter On My 99 Miata With 43k Miles Was Replaced A Month Ago. Last Week, The Check Engine Light Came On And I Pulled The...