Hi guys, I have a '96 Honda Accord EX 4 cylinder. I just do the emmission test in my state (washington) and failed. The engine light check is on and I already check it by short-circuiting the thing below the glove box. It came out as fault code: 80 or P0401 (EGR Flow Insufficient Detected) according to emmisssion check place. So, I buy a new EGR valve from honda dealer and replaced the EGR valve and reset the ECU but after run several miles, the engine light came back on. What do you think I should do? some of my friend suggest to take out the intake manifold and clean up all the carbon that might be deposited and block the passage flow to the EGR port. Any help will be appreciated. Thanks!

 

you can try and clean it but more than likely you will need to replace it, if you are hurting for money call a junkyard and get a used one just to pass smog

 

I already replaced the EGR valve but the engine check light still on :\

 

I would take the EGR Valve off and check the ports that lead to the intake. More than likely, there is just too much carbon build up and is not allowing enough exhaust flow into your intake. The exhaust gasses bring the temp of the combustion down, which in return, lowers the NOx levels in your emissions.

 

There was a nice post about it a month or two ago here with detailed pictures step-by-step. Just search.

 

thanks a lot for the info. However, do I need to replace the EGR valve gasket when I take off the EGR valve and clean up the port?

 

Depends on what shape it is in......if there is any doubt, replace it.