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So hey guys, so I've got an '06 Honda CR-V, no cat codes but both the front A/F sensor and the rear 02 mirror each other, which I was always told although the cat is not melted down and causing excessive back pressure, the cat can be bad no longer storing oxygen and I'm wondering if that's what I have going on here. Is there a way to test if the cat is still storing oxygen and if it's effective enough?
General rule if front O2 is switching hi-lo-hi-lo and the post cat O2 for that bank is the same pattern then the cat is it dosen't have to be melted just not working poisioned worn out or smashed from a back fire.,
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
Does the Catalyst monitor pass? If you clear the codes, can you repeatedly pass the Catalyst monitor?
To be honest, in cases like this, I let the car make the call. If the PCM is happy with the catalyst performance, I'm happy with the catalyst performance. Which is why I'm asking about the Catalyst monitor - if you can clear codes and make it pass consistently, I don't see a problem.
I have not got any codes for 02 or cat eff, it's just what I noticed while test driving with the live data pulled up. The car a alittle bit of a rough idle, which I should address of course. But I'm just preparing myself if this cat goes out, they're not cheap. I just can't remember how to do the oxygen storage test.
al514 wrote: I just can't remember how to do the oxygen storage test.
"Knowledge is a weapon. Arm yourself, well, before going to do battle."
"Understanding a question is half an answer." I have learned more by being wrong, than I have by being right.
What you witnessed on your test drive should be regarded as not a definitive reason to condem the cat converter.What you witnessed could be the result of having an out of range air fuel mixture that is overwhelming the cat with HC and CO and not containing enough o2 to carry out the conversion from co and hc into co2 and h20.Take a good look at your fuel trims because any thing more than 5% either way will indicate that you have a mixture problem that needs sorting.The cat will only operate correctly when the AFR lies within a very narrow range and this fact is even more important with a well used cat.On most of the vehicles i am asked to diagnose after failing the uk emissions test the problem is usually connected to having a old cat combined with out of spec fuel trims putting too much crap in and this inevitably means too much crap coming out.Without a EGA I admit it is not easy but if the fuel trims are in the range of 1 to 3% it usually follows that the Lambda readout is in the correct zone.Once the fuel trims are looking good then and only then blame the cat.
