I threw that code the other day while just cruising down the street at about 3.5K rpms but the batteries in my logger were dead so I didn't check it right away. When I was on my way to get some (next day), the light went back out. :scratch
What causes that code? too rich? too lean? I richened it up a little and now the car feels sluggish.

i threw that code in my 420a when i installed my turbo kit. my 02 sensor was bad, after i replaced that it fixed my code. i didn't understand it either. i did exactly what you did by richening up the car and got the same results. i'm not sure if the 02 sensor was at fault since i'm still tuning.

Originally posted by 98starGS
i threw that code in my 420a when i installed my turbo kit. my 02 sensor was bad, after i replaced that it fixed my code. i didn't understand it either. i did exactly what you did by richening up the car and got the same results. i'm not sure if the 02 sensor was at fault since i'm still tuning.

funny you mentioned the o2 sensor.
I think mine is on it's way out. When I hammer it, the o2 voltage is like .94v until about 5.5K and then it just drops all the way to .13v. It never shows any sign of being any leaner than it was at 3-4K other than the voltage being different. Doesn't misfire or knock. :shrug.

my car wasn't acting up either i didnt' know the 02 sensor was bad until i hooked up with a data logger. my blinky 02 gauge was reading just my tt narrow band was dead but it was acting like it wasn't warmed up.