67 Catalyst System Efficiency System below threshold, bad catalytic converter

This is the code I pulled off. But I don't have a cat so does that mean that my 2nd o2 is bad? Or maybe my IAC? Cause when I start my car in the morning it doesn't bring the idle up it just holds at 800rpm and then when the car is warm it idles at 1000-1100rpm. Any help you guys can provide is helpfull I would like to get all these problems straightend out before I attemp to tune the car.

 

I think it means your primary o2 is reading the same values as teh secondary, because you have no cat. And the ECU sees the values being the same, so it throws a code. Is your gas milage really bad? YOu have to run a cat in OBDII for this reason.

 

See I rode around with no cat for a year but this happened. But I changed the primary already I will change the secondary next. What about the idle problems what do you think? Oh and btw my gas milage is good but my car runs rich at idle all day

 

Rich problem...could be the o2 heater. Happened to me, the o2 would read, but only after driving around for awhile. What happened was thw o2 heater had failed and so the engine always thought the car was "cold" because the o2 never warmed up, so it dumped more fuel to compensate and try to warm it's self up with more fuel and a higher idle. So replace it and see, but I would get ahold of a scanner first and see what the valves are between the two o2's. Like you said, weird that it's just starting now after a year. Mine was fine for about a 3 weeks, then the code started coming up.

 

Thanks for your help now I need to get a hold of a scanner