I need help on how to clean the whole EGR system including ports, vacuum lines,tubes ect. My 1998 accord V6 got a rejection sticker at Massachusetts inspection. The tech said it was showing an EGR fail code. The engine light had been on for some time but the car still runs flawlessly and smooth.

I took off the top solenoid unit and blew out the chamber inside the solenoid and then cleaned the solenoid piston. (I did not test the solenoid piston as i do not know the procedure).

The housing that the EGR solenoid is mounted to has 2 openings, one round and one rectangle. They are part of a throat chamber that mounts to the right side of engine. I took a wire brush (similar to a gun barrel cleaning brush) and inserted it as far as it would go (4-5 inches) into the throat chamber and cleaned ot as much as I could. Because this air chamber housing is attached to the engine, I have no idea where the flow chambers go from there. I tried running flexible (springlike) odometer cable into the chamber but could only navigate the first bend. I vacuumed the carbon i got out and then tried to blow out the lines but the air didn' seem to flow through.

The honda dealer wants $510 for a new EGR and 3 hrs to clean the lines. I already had a shop who said they cleaned the EGR, but all they did was reset the EGR code. It was evident (no new wear on the bolt threads) they never even took off the EGR solenoid.

This is a great car! going to keep it forever. Is it worth replacing EGR solenoid with genuine honda part?

Thanks for helpful replies in advance.
PS I did check the posts and found only one other similiar with a link to pictures, but the engine was an earlier model and completely different, so no help.

 

Welcome!

I've never owned a V-6, so can't help you. It may be that you have to remove the intake manifold to clean the rest of the passageways. I'll move this to General Tech where it'll get more traffic. If someone comes up with a GOOD procedure, I'll move it back to DIY. You've actually got a good start here.

 

Well, I found a picture of the EGR valve, in with the thermostat housing. This thing (#8) bolts to the front head, so does that mean the EGR passageways are built into the head?

To remove that (#8) you'll have to drain the coolant, at least partway. I don't know whether that'll give you enough access to clean it out.

 

Jim, Thanks! That diagram is a big help. Notwithstanding any other advice from the General Tech side, I can always pull off #8 thermostat housing and try to follow the chambers that are not coolant lines.

Now I know why the Honda dealer wanted 3 hrs labor. Their tech said there were points that they actually drilled out the carbon with a bit. It would be good to know how to test the EGR to see if that part was working, or if it was just the lines that were clogged.

I'll keep you and the forum posted on my progress.

ttommy2tone

 

I think there should be a test to check the EGR valve (#1) is working. I never had a V-6, & never had EGR trouble with my 4-cyl, so I don't know. The on-line shop manuals (sticky thread in DIY secton) might be for 4-cyl, but maybe the test for the EGR valve is still valid.

But with 4-cyl engines (especially before 1997) it's more common for the passageways to plug up. So that's a kind of automatic first response when someone has an EGR problem.