LX 470 Catalytic converters gone bad. Help
- Thread starter Quick
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re_guderian
SILVER Star
I have a non OEM cat on my 2000, and it's works just fine. Pretty sure it was > $100, but whatever...
Quick,
Lol Have you just asked on Rennlist about the same problem?
It's pretty funny as I just advised you (I think) to come here...(I have a different name there)
Check the O2 sensors before replacing any cats !!!
Lol Have you just asked on Rennlist about the same problem?
It's pretty funny as I just advised you (I think) to come here...(I have a different name there)
Check the O2 sensors before replacing any cats !!!
Trunk Monkey
Moderator
Yeah, pretty rare for cats to go bad, unless you ignore an O2 issue forever.
How would you know if your cat had gone bad?
- Thread starter
- #8
What kind and where did you purchase it?
Too funny. What will we do without these boards? LOL
Actually common for cats to go bad especially for stop and go traffic cars. The Auto Zone code reader says, catalytic converters efficiency below yada yada and not to mention I have changed 2 O2 sensors in the last 2 years.
Read the above ^ reply and also truck running like crap (hesitating when accelerating) and no other codes besides the Cat convert?
Trunk Monkey
Moderator
First article I found Googling, but there's plenty more. Catalytic converter seller on Ebay:
http://www.ebay.com/gds/Reasons-for-catalytic-converter-failure-/10000000002803746/g.html
Cats don't fail, something else causes them to fail. Just pointing this out in case your cats have indeed become clogged, whatever is causing it will do the same to the new ones you put in.
http://www.ebay.com/gds/Reasons-for-catalytic-converter-failure-/10000000002803746/g.html
Cats don't fail, something else causes them to fail. Just pointing this out in case your cats have indeed become clogged, whatever is causing it will do the same to the new ones you put in.
re_guderian
SILVER Star
dunno, local exhaust place.
Quick,
When you changed your O2 sensors what brand did you use?
In my experience you should stick with Denso as some other ones can cause problems... just my $0.05
When you changed your O2 sensors what brand did you use?
In my experience you should stick with Denso as some other ones can cause problems... just my $0.05
- Thread starter
- #13
I always take care of my cars as promptly as I can. I bought the O2 sensors at Autozone, so not sure about the brand. Unliley for them to damage the cats though.
Checked with the master Toyota technician of several years and was told common for them to go bad as he has changed them quite often.
Per Toyota tech, common so not to worry about other things causing cats going bad. I have always, I mean always, used the premium gas and had recently (last year) spent over $1700 for a complete engine service including but not limited to changing the timing belt, water pump, plugs, fuel filter, all fluids changed including the AHC service to name few.
The link ^ does make sense and I think the problem could have been the O2 sensors bought at Auto Zone .
At autozone and dang it, they could have caused all these problems.
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It's possible. I've heard of aftermarket o2 sensors failing quick, but maybe more than one was out of whack enough to not set a DTC. I don't know much about how o2 sensors work together, but I know sometimes a new one with an old one can sometimes cause issues. If you replace with an aftermarket cat, don't be shocked with failure in a year or two.... But at OEM prices you could replace a lot of aftermarket cats.
Trunk Monkey
Moderator
If an o2 sensor is bad, that's exactly how catalytic converters get damaged. If there's a misread at those sensors and there's too much fuel or air getting into the exhaust it can clog or cook the cats, depending on what's out of balance. Again, if the cats are indeed bad, you need to find what caused that, they don't go bad all on their own. Your tech tells you it's "common", which it really isn't, but what you need to ask him if he thinks it's common - why is it common, what causes it? If he doesn't tell you it's an issue upstream, you need a new tech.
Someone asked how you can tell if your have a bad cat - that's the job of the o2 sensors. If the before cat sensors and after cat sensors don't jive for the ECU, one outcome if that symptom is left alone is damaged cats. Another possibility is physical damage, which could crack the ceramics inside the cat.
- Thread starter
- #16
Truck has almost 200,000 miles so mileage has nothing to do with the wear and tear on cats? I really can't think of any mechanical issues with the truck (out of tune/plugs/gas) etc that could have caused the cats destruction.
Would bad O2 sensors throw these codes (P0430 and P0420) which are catalytic converter efficiency codes?
Shall I check the O2 sensors even though there are no such related codes and how shall I test them?
On a same note, how can I check the A/R ratio to see if it's WNL (not tunning lean/rich) that could cause the cats damage?
Would bad O2 sensors throw these codes (P0430 and P0420) which are catalytic converter efficiency codes?
Shall I check the O2 sensors even though there are no such related codes and how shall I test them?
On a same note, how can I check the A/R ratio to see if it's WNL (not tunning lean/rich) that could cause the cats damage?
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Those two codes, 0430 and 0420, are cat efficiency codes, not cat failed codes. Both banks are reporting the same efficiency DTC so you have to find what the root cause is upstream. Likelihood of both cats just happening to fail without a common denominator issue is pretty slim. You need to look at your LT fuel trims and o2 sensor output voltages to start with. The fuel trim numbers will tell how much extra/less fuel is being delivered to maintain the ideal A/F ratio and the sensor outputs will show response voltages to varying engine/temp conditions. TechStream will do both for you and I'm sure there are plenty of OBD2 plug in Bluetooth monitors like scangauge (that I have no experience with) that will allow you to do much more extensive diagnostics. Certainly your cats could have been damaged by, say, burning coolant or a lead additive, but I'd eliminate potential upstream issues before swapping them out.
Have you considered simply replacing all 4 O2 sensors first? Denso sensors are only $44 on Amazon. That would eliminate them as both a source of the codes and as a cause of any other problem that would just recur if the sensors are bad.
- Thread starter
- #19
Update:
Dropped the car off at the mechanics who checked it out and called with the following results :
Hard to check the cats but I drove the truck with the scanner hooked up and it showed cyl 6 misfiring while the car was hesitating.
SO the good news, no cats for now .
Questions:
I only needed the boot for the cyl 6 but couldn't find one locally so ended up buying the entire coil. possible to get just the coil boots?
The truck has un named O2 sensors, do I go ahead and switch to Denso's?
Thanks all
Dropped the car off at the mechanics who checked it out and called with the following results :
Hard to check the cats but I drove the truck with the scanner hooked up and it showed cyl 6 misfiring while the car was hesitating.
SO the good news, no cats for now .
Questions:
I only needed the boot for the cyl 6 but couldn't find one locally so ended up buying the entire coil. possible to get just the coil boots?
The truck has un named O2 sensors, do I go ahead and switch to Denso's?
Thanks all
