1996 Honda Passport EGR question


Twinboom
01-15-2011, 05:57 PM
O.K., I joined the forum to find some concrete answers. I have read all posts regarding p0401, and P1406. I understand the EGR tube may need to be cleaned. What EXACTLY is the EGR tube? 1996 Honda Passpot, 3.2 V-6.

I removed the EGR valve and sprayed a can of cleaner through the intake hole. The error code P1406 still is active after clearing.

Do I remove the 90 degree part that attaches the valve to the intaker manifold, and is that "tube" everyone is referring to? Or, do I reove the tube that goes down to the exhaust manifold? Or both? Thanks, I took photo's and placed a red arrow pointing to the 90 degree part, and the exhaust tube. Hope it clarifies for future folks having the same issue. Thanks for any help!!!
Doug

danielsatur
01-15-2011, 06:03 PM
Yes - The EGR tube runs to the exhaust manifold.
You might need to take the throttle body off to clean the EGR
passages.

Twinboom
01-15-2011, 08:10 PM
OK, This is what I did. I pulled the EGR valve off the mounting point.

I removed the the body that attaches to the throttle body. It was totally impacted with carbon.

The hole that goes through the throttle body was also totally impacted.

I have taken pictures along the way to explain everything. When folks know what they are doing, it is not always explined thouroughly for those of us who don't do it for a living. No harm, no foul, it is what it is. : )

I cleaned out the 90 degree part that was attached to the throttle body after I removed it from the throttle body. Pictures show it. I then took a picture of the throttle body suction hole with the part removed. You can see it is totally impacted with carbon. I could not even get a wire to pass through that hole. After I cleared it, I stuck one of the long mounting screws that hold the 90degree part though the throttle body, and took a picture through the intake part of the throttle body, that clearly shows the screw sticking through the hole just above the fully open throttle plate. I put it all back together and cleared the codes, and they have not yet come back after running for 30 minutes in my driveway. I will come back and post a reply next weekend, as my job will not allow me to have it smogged before then. If ti come back ( p1406 ), then I will remove thew tube that goes down to the exhaust manifold and clean that. After finding how inpacted the part was that attaches between the throttle body and EGR valve, it seems pretty for sure with no flow coming through that hole, it is probably the culprit. I am an electrician by trade not a mechanic, but do everything I can to not give my money to someone else. The whole point is to assist others here, and I am glad this forum exists for us to be able to do so. Thank you mechanics for sharing your knowledge here. I only took it a step further so others could see exactly what i did to clear the problem. Maybe not the conventional way of doing it, but hoping it will cure the code issue stated. If anyone has any questions, feel free to PM me your phone number, and I will discuss it with you if need be to for clarification. I hope the pictures help.
I just ran out for some diner and the check engine light came on again, I will check the tube going down to the exhaust as "Danielsatur" suggested. Thanks againm, I will report bnack when I clean that out and let you know what happens.

Doug

Cat Fuzz
01-15-2011, 09:22 PM
The tube from the exhaust to the EGR is not likely to be clogged. The clog always happens in the passage from the EGR to the intake. Wherever that tube dumps in the intake is where it will clog. The reason is particulate matter from the exhaust mixes with the oil residue coming from the crankcase PCV system and sticks to the outlet of the tube eventually clogging it up. I'm not sure on your year but my newer engine requires the removal of the throttle body to gain access to the end of the tube. I know you have a different intake setup than I have. The EGR system does nothing while the engine is at an idle so you could idle the engine until you burn a tank of fuel and the light won't come on. EGR faults only show up as the car is being driven.

Twinboom
01-15-2011, 09:31 PM
For some reason trying to post additional pictures is not working. ...........so....I removed the tube that goes down to the exhaust manifold. It was clear as can be. The problem....I broke both of the flange bolts that hold it to the exhaust manifold :crying:, so I will have to remove the left side exhaust manifold I am thinking to be able to drill them out, and repair with a heli-coil set up. Bummer.

Mr. mechanics, knowing now that the intake is totally clear, and the down tube to the exhaust manifold is also clear, any thoughts on what the issues now might be? The code coming back is still the P1406 code. The EGR is brand new.

I'll deal with the broken bolts tomorrow. Hope I can get them repaired before Tuesday when i go back to work, or hope that the weather stays clear so I don't need my 4x4. I work up in Lake Arrowhead in the San Bernardino mountains. OK, that's my story, looking for some sort of happy ending here... : )

Your thoughts on this one would definately be appreciated. The car had not cooled off yet after going out for dinner, which may have led to the bolts snapping off...maybe :disappoin

Doug
:)

Twinboom
01-15-2011, 09:35 PM
The tube from the exhaust to the EGR is not likely to be clogged. The clog always happens in the passage from the EGR to the intake. Wherever that tube dumps in the intake is where it will clog. The reason is particulate matter from the exhaust mixes with the oil residue coming from the crankcase PCV system and sticks to the outlet of the tube eventually clogging it up. I'm not sure on your year but my newer engine requires the removal of the throttle body to gain access to the end of the tube. I know you have a different intake setup than I have. The EGR system does nothing while the engine is at an idle so you could idle the engine until you burn a tank of fuel and the light won't come on. EGR faults only show up as the car is being driven.

Wish I would have read this post before I busted the two bolts off. Life goes on, maybe this will keep someone else from doing the same thing. I DO APPRECIATE all the advice regardless though. Things happen.....if your not making mistakes, you are not moving....sometimes : )

Doug

Cat Fuzz
01-15-2011, 10:31 PM
That code refers to the pintle position circuit. To me this seems more like a wiring problem. Check you connections and ground. Check that the "can" of the EGR valve has continuity to battery negative. Check that the red wire to the EGR has 5 volts when the key is on, engine off.

Twinboom
01-16-2011, 09:14 AM
That code refers to the pintle position circuit. To me this seems more like a wiring problem. Check you connections and ground. Check that the "can" of the EGR valve has continuity to battery negative. Check that the red wire to the EGR has 5 volts when the key is on, engine off.


I have a pretty nice DVM, and checked the positive terminal of battery to the can. Assuming that is the outside of the EGR. 12.79 volts, which is what the battery shows across both positive and negative. negative to first pin on connector shows 11.96 volts, and the second pin which I think is the red wire connection, kind of hard to tell, is 5.06 vdc. I do appreciate your tips....

Doug

Twinboom
01-20-2011, 12:00 AM
I got the manifold back on, and will try and drop off the car this weekend to see what they smog guys say. I'll let you know so we can wrap this one up. Later,

Doug

Twinboom
01-28-2011, 10:35 PM
I got the manifold back on, and will try and drop off the car this weekend to see what they smog guys say. I'll let you know so we can wrap this one up. Later,

Doug

I took my car in as the code p1406 would not go away and kept coming back as soon as I went a couple of blocks. I took it to a local mechanic last Saturday, 1/22/2011, and after checking things out, he felt it was the new EGR valve I had installed a few weeks earlier. I took it back to the parts store, (I still had the receipt), and when he re-installed the second new valve, it worked like a charm and has not had any issues, and passed the smog test as well the following Sunday after a I put some miles on the car.

So, I cleaned out the intake egr orifice between the EGR and intake manifold, it was totally clogged. I broke the bolts on the flange that attaches to the exhaust manifold. A local machine shop got two of them out along with an exhaust manifold flange stud that also broked removing the exhaust system. I then put it all back together, had a mechaninc check it all, and replaced the new EGR valve, the original replacement was in fact bad, and now it is all happy again. Now you know the rest of the story. I tried to post some photo's of the cleaning process, but was not able to DL them for some reason. I'll try again at the end of this post. Take care,

Doug Blackburn
Yucaipa California

P.S. I still cannot get JPEG's to oad for some reason. They did in the first post, but nothing after that. Oh well. HOpe the information helps, if not, PM me and I will share with you how I cleaned stuff up. Later,:p

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