Failed at 15 nox 1241,CO.02%HC5ppm,CO2 15%,O2 0%.25mph NOX 969,CO .02%,HC 2 ppm,CO2 15%,O2 0%.After plugs & decarb Nox 700,cold or hot [...] vac leaks found . LLTFT is -2%.F/P & flow is good ,no [...] [...] O2 sensor, was biased lean,replaced, no [...] cat nox... Login to read more.