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From: VA

I recently just purchased a 2006 IS250. It has been giving me a P0420 and P0430 code. I have replaced both sensors as well as both Cats. Still getting a cel like with the same codes. Any recommendations or fixes anyone knows about?

Thanks.

Joined: Mar 2011

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From: South Carolina

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From: VA

i used OEM cats and Denso o2 sensors. Replaced both downstream and both cats. Just rechecked code after replacement and it’s actually P0171, system too lean. Now I’m thinking it’s either the upstream sensor, plugs n wires, or MAF sensor.

Joined: Mar 2011

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From: South Carolina

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From: VA

Okay, I’ll give it a shot. I’ll likely do a full time up as well. I will update once completed. Thanks

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From: OR

Joined: Mar 2011

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From: South Carolina

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From: VA

no no vacuum leaks. Cleaned MAF sensor, no luck. Replaced both upstream sensors. So far so good but it’s only been a day so I’ll give it more time and repost an update. Any other suggestions?

Joined: Mar 2011

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From: South Carolina

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From: VA

yes both sensors replaced. No CELs

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From: TX