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P0401 Passage Cleaning?

04-21-2011, 08:12 PM
2000 accord ULEV

Now before we get in to this, I know what the P0401 is and I know that the EGR valve is ok. I Ohm'd the EGR valve and got 1.7k ohms from pins 1 & 2 and 3.7k ohms from 1 & 3. The snap-on scanner said that if it was over 100k ohms suspect the EGR valve but since those numbers seem to be ok I figured the passages need a good cleaning. I have read some of the other threads and i'm aware that you need to take the intake off to do the cleaning correctly. I have also seen that you need to drill and tap in tubes in the clogged passages. Im wondering if anyone has performed this and what procedures where used and what you used as tubes to tap in... thanks for the advise! :iceslolan

04-21-2011, 11:41 PM
I'm guessing you are talking about a V6, since that is the one where the tube is inserted. You buy a kit from Honda that includes a new EGR valve & gasket, throttle body gasket, intake gasket, and tube. Once the throttle body is removed from the intake, the intake is removed. The special drill bit is NOT included in the kit and available through Honda. You clean out the passage as best as possible then drill it with the bit and install the tube with a special driver that is also included with the bit. After that remove the old EGR valve and clean that port as best as possible. Then reassemble. It's fairly easy if you have all the right tools(drill bit & tube installer) I have not tried to fix this issue any other way besides the correct way as stated by Honda's TSB.

If you are talking about a 4cyl that is a whole different story. That one is pretty easy too. There is a plate you can remove on the intake and then you clean the port. There is not EGR kit available that I know of.

04-22-2011, 08:02 PM
im sorry that i didnt post that it is a 4 cyl... do you know if honda sells a kit for the 4 cyl???

04-22-2011, 08:25 PM
No there is not a 4cyl kit I know of. I suggest from past experience remove the intake cover. I think there is about 8 bolts or It's the rectangle plate on top. Remove the EGR valve, get a new gasket and possibly a new valve. You will see a ton of carbon. Soak it with carb cleaner from both ends, intake and EGR valve holes. Let is sit for a little then use a coat hanger to clean the passage. Repeat until clean. If you have access to compressor blow air through each time and cover with a rag. The black stuff will blow all over and make a mess. You shouldn't need a new gasket for the intake plate because it's metal and should be reuseable.

04-22-2011, 08:29 PM
After looking at the diagram yours doesn't have the plate I was thinking of but it does seperate. I will suggest a throttle body gasket too since you will need to remove that from the upper intake to make it easier. You don't have to take it off but if you leave the hoses connected you won't have to worry about coolant loss and all that goes with it. Here is a pic, you will need to remove #10 to get to the EGR passage way.

04-22-2011, 08:59 PM
thanks i have to replace my brothers master cylinder tomorrow morning then may tackle this after if i do ill let you know how i make out!!!

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