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Emissions Component

1996 Isuzu Trooper, 3.2 litre V6. Has an OBD code of 401. How can I get this to pass smog?

This issue seems so ambigous. I just want it honestly diagnosed, repaired and to pass inspection. The 401 code refers to the EGR valve, which to my understanding has been replaced. The gas cap has also been replaced. The code was cleared, but returns. The vehicle is has had all DMV fees paid and is on a temporary registration, which expires soon. The car has had a lot of work done to make it roadworthy as it was recently inherited from my wife's brother having passed away. It is still in his name as probate is happening. However, she as the administrator has authority over the vehicle. It initially had sat idle for over a year. In general, after several other repairs it seems like a fine daily driver, but we need to get past this smog test hurdle. I don't really want to or have a bunch more money to throw at this vehicle. Where should I take it? What should I do? Please advise. Thanks so much.


It is true, P0401 does refer to you Isuzu Trooper's EGR valve. P0401 can be triggered by carbon buildup within the EGR valve passages. Although the EGR valve may have been replaced, the EGR system may still be dysfunctional.

posted by SmogTips Support 04-01-2011 08:06 PM

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