1. Home
  2. Toyota Camry
  3. Cleaning of Camry EGR Valve?

Cleaning of Camry EGR Valve?

Today was emissions check day. Unfortunately, the car failed. HC is great. CO is great. CO+CO is fine. The only problem is NOx. Last year, it barely passed this, so this issue was not unexpected.

This happened a few years ago and a cleaning of the EGR by my mechanic brought it in line. Today, the emissions tech said the EGR would be the first thing to check given my particular problem. I was able to pretty much disassemble the EGR valve on my 91 2.5L V6 tonight. Everything looked like it was going to come apart just fine when I suddenly remembered I had to be able to use my car tonight, so I put it back together. I really didn't get a chance to look inside the passageways to determine the level of blockage. Tomorrow, I plan to take it all apart again. I am wondering how one actually cleans these once they are off the car. One past post said they used rope. Did you thread that through the EGR valve? What about the down pipe going to the manifold - do you just loosen the blockage by jamming the rope into the pipe? What about if the junk falls into the manifold? It seem like it might cause problems with things downstream in the exhaust system? I have a can of oxy-sensor safe throttle body cleaner. Should I spray that into the EGR passageways? I am guessing you don't want to spray that into the connecting down pipe leading directly into to the manifold???

Any tips or pointers would be appreciated!

Thanks in advance, Doug

Reply to
-
Loading thread data ...

Remove the EGR valve. Set the valve aside. There are two ports in the EGR mounting surface. One goes to the intake manifold and of course, the other to the exhaust. You want to poke out the exhaust supply passage with WHATEVER gets the job done. A stiff piece of wire (coat hanger) works for me. Work at it until you know you've broken thru the occlusion. With the EGR valve still removed, you may start the car for just a moment and then shut it off. This will clear the exhaust passage nicely. (Expect the engine to race ... shut it down after only a second). Reassemble.

--

- Philip @ Maximum Torque RPM
Reply to
Philip®

Thanks for the info., Phil.

I took it all apart again this morning. To me, it doesn't look like the massive clogging I expected if the EGR were the source of my NOx emission error. If any experts could please look at the digital snaps I took and give me an opinion, I would appreciate it. Here is the link. There are three pictures on this page that are about 60K each. They pop up at once, so please wait about 20 seconds for them to download if you are on dial-up.

formatting link

I did really soak and drain the EGR chamber a few times with throttle-body cleaner. I don't know if it helped but it didn't seem like I felt any clogs "around the bend" in the chamber.

The port on the TB was not clogged any more than the other three ports shown in the pictures (I could not get the camera in position for a decent shot). It looked clear as far as I could see and feel. I shot TB cleaner in it and it did not backflow/ fill up.

My spark plugs have 63k on them. The car idles fairly smoothly and accelerates just fine. Old plugs wouldn't really affect NOx that much, would they?

The EGR modulator seemed to function as the book said it should when blowing air through it. I used compressed air to blow out the filter material.

Unless I unclogged things with the TB cleaning fluid, I don't think anything has been solved and hate to waste my 1 free re-inspection. Any thoughts would be appreciated.

Thanks in advance, Doug

Reply to
-

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.