So I am getting the P0401 code on the car. Its a 2001 EX sedan with 240k miles on it. Took the EGR off and cleaned it and installed a new gasket along with. Same code still pops up. Unplugged the EGR and its NOT stalling on idle (so I got a clogged EGR port(s) somewhere). These do not have the EGR runners above the intake manifold that were on my prelude and older civic I had. Anybody have an idea where to start or should I just take off the intake manifold along with the throttle body and clean them?

 

Clean the passage under the EGR, your pretty much gonna have to scrub the carbon off. Try cleaning the throttlebody and intake while on the car. Also, a couple of people have reported clogged ports further in the engine so, you may end up taking them off anyways.

 

When I removed the intake from my 225k miles beast the ports in the injector plate were clogged with carbon. I had to soak with solvent, scrape, and brush it out.

Looking at this pic I stole from this site.



Those passages around the intake openings.

 

hello,i am having the same problem with my 2002 civic ex,this the number 4 spray can i sprayed in the egr intake ports.is a pain.they say to scrub ,code keep coming back.on my own post i am looking for info about removing the whole small block where the erg seat,i let you know.

 

i'm gonna throw some seafoam in it the next time I take it off to see if that helps. Already ran it through my vacuum hose, but it didn't help the EGR out any. Cleaned up my idle some, but didn't do anything to help the EGR.