Catalytic converter compatibility?

[Peacefrog]

I am currently getting a PO420 code on my 2002 Echo and have had my catalytic converter replaced (at Midas) with a 3rd party converter three times over the past few months. The most recent replacement was last Tuesday and I was told that the converter was being replaced with a different brand of converter but if this one didn’t work I would need to pay them the difference for a Toyota converter. Like clockwork the PO420 code popped back up this morning so I started looking into the OEM converter to discover that it is VERY much more expensive than the 3rd party units.

Does anyone know if there is a known compatibility problem with the Echo and 3rd party cats?

I have also replaced the bank 1 sensor 2 in the past several months if that matters.

Greg

[toyomoho]

P0420 usually means there is a problem with the 02 (A/F) sensors, their circuits (wiring) or the CAT. The 02 (A/F) sensor signals before and after the CAT are compared by the ECU. This allows determining the efficiency of the CAT. If the signals are the same amplitude, the ECU thinks either the sensors are bad, the circuit or the CAT is operating below efficiency. It does not know specifically which part is bad.

Typically if an A/F sensor this code and another A/F sensor code would also show up. However it still may be either of the A/F sensors, there is one the exhaust manifold and one after the CAT.

Have not heard of issues with using after market CAT’s although sometimes one aftermarket A/F sensor can cause more issues (codes thrown) then others.

Are there any codes besides this one coming up, any leaks in the exhaust system, check both A/F sensors for operation.

How many miles on this car? The EPA mandates an 8 year/80K mile warranty on the CAT. If you meet this criteria and it is the CAT have Toyota replace it at no charge.

[Peacefrog]

Thanks for your reply. I have checked the various sensors in front of and behind the cat and did find one that needed replacing (bank 1 sensor 2; the one after the catalytic converter) so I think it might not be the sensor (though it sure would be less expensive if it were it seems). I have suggested to the people that the wiring might have a problem and they are very insistent that it is not. As far as I can tell they have not checked it and I am not sure how to go about checking it either. The new catalytic converters should be good as they are new. The last one has only about 150 miles on it. The original catalytic converter that came with the car lasted to a little over 130K miles. The car now has just under 157K miles on it now and has gone through four catalytic converters (all third party ones from Midas) during the last 27K miles. I only paid for the first one and the ones after that were covered under the warranty for the first one.

The cat that Midas installed ran ~$300 and now they are telling me that they don’t want to replace it with the same part again and want me to pay the difference for an OEM part. I got a quote for the OEM part of $927.54. Midas is making the argument that my car is simply not compatible with 3rd party cats but so far I have not found any information that suggests that this is indeed true.

At this time the only code that is coming up is the PO420

I will suggest that they check for leaks in the exhaust system.

Greg

[echo987]

Oxygen sensor before the cat might need to be replaced also. they should both be replaced at about 100K.

[JamesBond007]

Originally Posted by echo987

Oxygen sensor before the cat might need to be replaced also. they should both be replaced at about 100K.

I'm also having the same issue w/ my '95 Tercel (getting the P0420 code). I replaced the oxygen sensor after the converter, but after several 150+ mile trips the check engine light is still on. Should the light go off automatically once the problem is fixed or does the computer/error code need to be cleared/reset somehow?

[rmlrobl]

I know this is an older thread, but I just bought a used 2000 Echo. I got this samer error code four days after I bought it. I already ordered spark plugs for it. But I assume it has more to do with the CAT. Any updates on what fixed it??

[JamesBond007]

Originally Posted by rmlrobl

I know this is an older thread, but I just bought a used 2000 Echo. I got this samer error code four days after I bought it. I already ordered spark plugs for it. But I assume it has more to do with the CAT. Any updates on what fixed it??

I ended up replacing the other O2 sensor (the one before the converter) and that fixed the problem - no need to pay for a pricey new CAT or deal with installing it. Good luck!

[rmlrobl]

Originally Posted by JamesBond007

I ended up replacing the other O2 sensor (the one before the converter) and that fixed the problem - no need to pay for a pricey new CAT or deal with installing it. Good luck!

THANKS, will go give it a shot. Let ya know if it works!!

[rmlrobl]

is it the 1 wire or 3 wire sensor? If I may, where did you get yours and for how much $$??

[rmlrobl]

while I am at it, is it MANDATORY to have both CATs or can you go with just one?? Curious?

[ToTo_17]

I think its the three wire sensor...

[Stevo_Echohb05]

Originally Posted by echo987

Oxygen sensor before the cat might need to be replaced also. they should both be replaced at about 100K.

NO