i have a chevy 350 1 ton year 2000 and the cat sensor won't reset when driving between 40 and 45 for long over 5 miles continuesly the smog guy says he doesn't see any bad numbers its only the catsens
Those cats need to get really hot to reach testing temperatures.
Maybe you need to replace the O2 sensor or complete a drive cycle. Look up how to do a drive cycle.
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