04 civic 404/420 codes
If you think a good mechanic is expensive, try hiring a bad one
Joined: Dec 2011
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From: Midwest. Aiming about mid-chest
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Re: 04 civic 404/420 codes
How about posting the entire code next time.
P0404 is EGR valve insufficient lift, the PCM didn't see the desired change in sensor voltage when it commanded the EGR valve to open.
P0420 is cat inefficiency.
P0404 is EGR valve insufficient lift, the PCM didn't see the desired change in sensor voltage when it commanded the EGR valve to open.
P0420 is cat inefficiency.
If you think a good mechanic is expensive, try hiring a bad one
Joined: Dec 2011
Posts: 32,017
Likes: 256
From: Midwest. Aiming about mid-chest
Rep Power: 518 Re: 04 civic 404/420 codes
Not necessarily.
The EGR needs diagnosed first.
Then fixed for whatever caused it.
Clear codes.
See if the cat code comes back, before condemning it. Then figure that one out (not always a bad cat, but usually is).
The EGR needs diagnosed first.
Then fixed for whatever caused it.
Clear codes.
See if the cat code comes back, before condemning it. Then figure that one out (not always a bad cat, but usually is).
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