I have a '97 grand cherokee, inline 6.
I recently got a actron scan tool! (Yippee! I think...) While checking for stored codes, I found that when listing the IM monitors, the Catalyst monitor comes back as 'not ready.' The others are either 'ready' or 'not applicable.' Unfortunately, the handbook gives very little info about the monitors. From the sound of it, I would guess this to be related to monitoring the O2 sensors, but I have had no error codes in the computer that would indicate a problem with them. (Or could it be no error codes because it is not monitoring them?) I have allowed the engine to reach full operating temperature, and driven it for about 10 to 15 minutes, and still get the 'not ready.' Any ideas, or has anyone had this problem before? thanks...
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