1999 Ex P0420 and P0430
#1
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It's been a bad week for this car. 1999 Civic EX with 123,xxx miles started throwing the P0420 and P0430 codes after I put a starter in it. Earlier in the week it also got a new distributor. I've tried looking around and I can't seem to get any answers for my specific car and for both codes at the same time. Any ideas?
#2
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P0420 Catalyst System Efficiency Below Threshold (Bank 1)
There are a number of things that could be causing this p0420 catalyst efficiency code. The most common thing is the catalytic converter itself is no longer functioning properly. The other likely thing is the rear O2 (oxygen) sensor is no longer working properly. Other things could include exhaust leaks, damaged exhaust pipes, damaged O2 sensor wiring/connectors, plugged catalytic converter, etc.
P0430 Catalyst System Efficiency Below Threshold (Bank 2)
A code P0430 may mean that one or more of the following has happened: The catalytic converter is no longer functioning properly An oxygen sensor is not reading (functioning) properly There is an exhaust leak
Don't see how changing a starter can cause these.
There are a number of things that could be causing this p0420 catalyst efficiency code. The most common thing is the catalytic converter itself is no longer functioning properly. The other likely thing is the rear O2 (oxygen) sensor is no longer working properly. Other things could include exhaust leaks, damaged exhaust pipes, damaged O2 sensor wiring/connectors, plugged catalytic converter, etc.
P0430 Catalyst System Efficiency Below Threshold (Bank 2)
A code P0430 may mean that one or more of the following has happened: The catalytic converter is no longer functioning properly An oxygen sensor is not reading (functioning) properly There is an exhaust leak
Don't see how changing a starter can cause these.
#4
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http://engine-codes.com/p0430_honda.html
Possible causes
- Three way catalyst converter Bank 2
- Exhaust tube
- Intake air leaks
- Fuel injectors may be faulty
- Fuel injector leaks
- Spark plugs may be faulty
- Improper ignition timing
- Engine Control Module (ECM)
Possible causes
- Three way catalyst converter Bank 2
- Exhaust tube
- Intake air leaks
- Fuel injectors may be faulty
- Fuel injector leaks
- Spark plugs may be faulty
- Improper ignition timing
- Engine Control Module (ECM)
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