Last week I failed the State of WA emissions exam. I contacted a few shops and was told by a couple of them that it would cost about $300 to repair (seems high to me). One shop said that I may not have to replace the EGR but most like just need it to be unclogged. Can you tell me how difficult it is to replace the EGR on a 99 Honda Accord 4 Cyl. and if any special tools are required. Also, I'd like to know if it is difficult to attempt unclogging the EGR line. If not, any tips on how to do this (a diagram would be appreciated)?

 

If you look through the posts on the first few pages here, you will see a few threads on failed emissions and EGR cleaning, etc. I, personally, have posted a couple.

In all likelihood, it's your EGR ports that need to be cleaned (being clogged with carbon). If you are somewhat mechanically inclined, it is a fairly straight-forward job, and should take you about 2.5-3 hours or so. I just did mine.

I failed my GA emissions with high NO ppm and CO%. The EGR system generally causes this. Depending on the mileage on your car, it's probably just clogged EGR ports. I, and others, have posted how to's on the forum here on the matter.

BTW... Since I cleaned my EGR ports, I retested and passed emissions this time with flying colors.

To answer your questions specifically, you'll want a small flathead screwdriver or a pick of some sort, carb cleaner, q-tips, and your other normal tools like sockets and wrenches, etc. to do the job. A shop vac to suck out the carbon as you go really helps too.

You will want to replace at least the o-rings and maybe even the seal rings for your fuel injectors too as they will come out when you do the port cleaning job. You have to take off the fuel rail to reach the EGR ports.

If you do have a bad EGR valve and you want to replace it yourself, you will need an EGR valve gasket to replace the old one with. If it is your valve causing the issue(s) and not the clogged ports, you may just need to remove the valve, clean the carbon out of it, and then replace its gasket. It's two bolts to the the EGR valve off itself. Try that before buying a new one. But it probably is just your ports that need to be cleaned out.

 

I highly doubt you need to replace the EGR valve itself. Do a search in addition to what jobrien explained. Unless you have no tools or are completely mechanically incapable, it's a pretty easy job to do yourself provided you're patient with it.