Catalyst system efficency below threshold?
karnovking
11-07-2008, 04:33 PM
My 01 Odyessy is reading code PO420 Catalyst system efficency below threshold.
Can someone tell me what this means?
Can someone tell me what this means?
UncleBob
11-10-2008, 12:55 AM
My 01 Odyessy is reading code PO420 Catalyst system efficency below threshold.
Can someone tell me what this means?
it means your cat is bad, most likely.
Can someone tell me what this means?
it means your cat is bad, most likely.
shorod
11-10-2008, 08:15 AM
There are a few items that can cause such a diagnostic code. Check the following before condemning any one part:
Use of leaded fuel
Damaged HO2S
Malfunctioning ECT
High fuel pressure
Damaged exhaust manifold
Damaged catalytic converter
Oil contamination
Cylinder misfiring
Downstream HO2S wires improperly connected
Damaged exhaust system pipe
Damaged muffler/tailpipe assembly
Retarded spark timingDoes your van run fine, or seem low on power?
You should also search the Odyssey forum for the code to see if there are common causes for this code on your specific vehicle.
-Rod
Use of leaded fuel
Damaged HO2S
Malfunctioning ECT
High fuel pressure
Damaged exhaust manifold
Damaged catalytic converter
Oil contamination
Cylinder misfiring
Downstream HO2S wires improperly connected
Damaged exhaust system pipe
Damaged muffler/tailpipe assembly
Retarded spark timingDoes your van run fine, or seem low on power?
You should also search the Odyssey forum for the code to see if there are common causes for this code on your specific vehicle.
-Rod
karnovking
11-11-2008, 08:26 PM
yeah, it runs fine. I cleared the code. Have taken the van about 200 miles now and the code has not come back. so i'm now playing "wait and see"
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