This is a detailed video on how to clean EGR Passages and throttle body in V6 3.0 engine. The car is 2001 v6 3.0 accord coupe. This is J series V6 that was also used on Acuras (1998, 1999, 2000, 2001, 2002).
P0401 could mean one of the following:
1) Differential Pressure Feedback EGR sensor is faulty
2) There is a blockage in the EGR passage, most likely carbon buildup
3) The EGR valve is faulty
4) The EGR valve may not be opening due to a lack of vaccuum

Recommended tools:
1. Screw driver set: https://amzn.to/2XAk3sH
2. Sockets and wrenches set: https://amzn.to/36xLnMn
3. Pliers: https://amzn.to/2U4rY0q
4. Carb cleaner: https://amzn.to/2XUfmtY

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