Re: HCH2 EGR Port Cleaning - HOWTO
 

It's me. I moved them from the target location.

Fixed

Re: HCH2 EGR Port Cleaning - HOWTO
 

I had a P0404 CEL light. I initially cleaned the EGR valve but the CEL came back immediately. I proceeded to replaced the EGR valve and the car ran fine for a few days but the CEL light returned. I did have the symptoms of the light pinging at cruise and at light throttle. I followed the instructions on this post and found that all four ports on the EGR chamber was block! I have attached photos before the cleaning! I followed your instructions and throughly clean and reassembled the EGR chamber. I am sure this will solve my CEL light but I will report back in a few days.

Not sure if the EGR replacement was necessary or does a failed EGR cause this type of carbon built-up?

Thanks for the informative post.

Jeff
https://cimg0.ibsrv.net/gimg/www.gre...98bb38e063.jpg
https://cimg2.ibsrv.net/gimg/www.gre...c2a05da16d.jpg

Re: HCH2 EGR Port Cleaning - HOWTO
 

I did not have to replace my EGR. Port clogging is a symptom of use/miles.

Re: HCH2 EGR Port Cleaning - HOWTO
 

Meant to post earlier ... really nice info ... I did my ports and got out a lot of carbon, even though I could see each of the four holes was still open. Car runs great, thanks all!

Re: HCH2 EGR Port Cleaning - HOWTO
 

Re: HCH2 EGR Port Cleaning - HOWTO
 

Wish granted. What are you? 12? :P

Re: HCH2 EGR Port Cleaning - HOWTO
 

Oh man... ! thanks for this info..

my 2006 Civic hybrid has 225,000 plus miles and have had pinging for about the last 20k miles..

had 1/2 inch of Carbon build up .. both inner cover and lower 4 holes were filled and i had to chisel it all out and now super excited to see how this improvement will result !

Re: HCH2 EGR Port Cleaning - HOWTO
 

So how badly have I messed up?

Im reading this thread and looking at the Dropbox pics AFTER I cleaned the EGR ports yesterday.

I wasn’t very cautious about letting the loosened debris fall into the coolant as I now see I should have been.

The car runs fine so far (I only drove it a little yesterday after cleaning the Egr chamber, and then a little again today after changing the spark plugs) but I have a small coolant leak from a small hose just below the Egr valve. Maybe related to me contaminating the coolant, I don’t know. I don’t even know what the hose is or where it goes to/from. I’m pretty sure it wasn’t leaking before. But my bigger concern is what is the potential damage from the loosened carbon debris having gotten into those channels?
I wish I’d consulted this thread and those pics before I did the job!

Re: HCH2 EGR Port Cleaning - HOWTO
 

I would do a coolant flush as soon as possible. The carbon is typically a fine powder or flakes. I doubt it would cause any major issues.

Re: HCH2 EGR Port Cleaning - HOWTO
 

Thanks for the quick response- and for posting the how-to originally!
When you say flush, do you mean simply a drain and refill or a more involved flushing of the entire system?