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Recent questions tagged p0421

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1 answer 310 views

engine light came on, did diagnostic code: P0421

asked Dec 6, 2017 by anonymous

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2 answers 804 views

Have both P0421 and P0431 engine codes at the same time no others show up where to start?

asked Nov 1, 2017 by anonymous

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1 answer 440 views

Is that possible that both catalyst converters go bad at the same time?

asked Oct 20, 2017 by anonymous

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1 answer 516 views

On a 1994 Mitsubishi Endeavour, what does the engine codes P0421, P0431 and P0301 mean?

asked Aug 26, 2017 by raul

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1 answer 336 views

Just did valve job and now it is setting a P0421 code

asked Jun 27, 2017 by anonymous

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1 answer 761 views

what is the chance that codes P0431 and P0421 only needs the sensors replaced

asked Jun 5, 2017 by anonymous

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0 answers 510 views

2000 Mazda Protege P01450 repair cost?

asked Apr 16, 2017 by anonymous

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1 answer 1.0k views

I have a P0431 and P0421 code, for a 2003 Kia Sedona XE. what should I do?

asked Mar 16, 2017 by anonymous

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1 answer 663 views

My 2002 Mitsubishi Diamante 3.5L V6 came up with the P0421 and P0305 codes, what does it mean?

asked Mar 16, 2017 by anonymous

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1 answer 513 views

2004 Mitsubishi Lancer Ralliart 2.0L with engine code P0421, what needs to be fixed?

asked Mar 6, 2017 by anonymous

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1 answer 311 views

Coul you tell me if both sensors oxygen are the same or diferent thanks

asked Feb 14, 2017 by Ricardo

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1 answer 765 views

I replace o2 sensor upstream should I replace sensor downstream too?

asked Jan 30, 2017 by Ryozo

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1 answer 2.6k views

04 kia codes p0431 & p0421 what else can be done other then intake?

asked Jan 25, 2017 by anonymous

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1 answer 722 views

P0401 & P0421 Lancer 02

asked Jan 24, 2017 by anonymous

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1 answer 633 views

could not tightening gas cap cause p0421 & p00446 come on in a Hyundai sonata

asked Jan 21, 2017 by anonymous

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1 answer 644 views

P0421 Mazda - What systematic diagnostic tests or procedures would best confirm the root cause?

asked Jan 15, 2017 by Tosh

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0 answers 405 views

P0421 Mitsubishi - eclips

asked Dec 21, 2016 by anonymous

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