On most Camry NOx failures, all I had to do was to take off the two nuts holding the valve to the back of the intake manifold (4 cyl) and poke the carbon buildup inwards with a screwdriver. It will appear to be (in a mirror) a crust black area between the threaded studs. Create a hole, button it up, and head back to the dyno.
clean or replace egr valve
well i had my egr valve for close to 20 years its time for me to either clean it or replace it. I just had an emissions test the nitrogen was high, so probably the egr, i dont think its the cat converter.
not sure how the egr thing works would it be just as good as new if cleaned of all the carbon or would it be some what not as reliable as a new one after cleaning.
not sure how the egr thing works would it be just as good as new if cleaned of all the carbon or would it be some what not as reliable as a new one after cleaning.
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sounds good ill give that a try, i may have to see if any of the wires leading up to egr valve are plugged up as well. ill have to try to push a wire hanger up it. i think the limit on NOX was 2.00 and I was at 1.90 i knew something wasnt right egr valve
manifold side or valve side?timebuilder said:On most Camry NOx failures, all I had to do was to take off the two nuts holding the valve to the back of the intake manifold (4 cyl) and poke the carbon buildup inwards with a screwdriver. It will appear to be (in a mirror) a crust black area between the threaded studs. Create a hole, button it up, and head back to the dyno.
Also, did you replace the egr valve gasket when doing this?
before you do anything do this, get a hose, get the car idling and put one end on the valve and the other in your mouth and suck the valve open, the motor will go nuts if its working
I jUSt pulled the egr valve and tube, and low and behold, there was a huge rock of carbon plugging up where the valve meets the fuel intake
It popped out easily. I then cleaned out the egr with deep creep........all is good!
I love working on these cars, it took me all of ten minutes to do!
When I had my Mercury Grand Marquis, dealing with the egr/egr tube setup was the biggest P.I.T.A.!
It popped out easily. I then cleaned out the egr with deep creep........all is good!
I love working on these cars, it took me all of ten minutes to do!
When I had my Mercury Grand Marquis, dealing with the egr/egr tube setup was the biggest P.I.T.A.!
10 min sounds good, glad i had u think about it!IvanHoe said:I jUSt pulled the egr valve and tube, and low and behold, there was a huge rock of carbon plugging up where the valve meets the fuel intake
It popped out easily. I then cleaned out the egr with deep creep........all is good!
I love working on these cars, it took me all of ten minutes to do!
When I had my Mercury Grand Marquis, dealing with the egr/egr tube setup was the biggest P.I.T.A.!
make sure u put a new gasket
yup, if it wasnt for your thread, I wouldve never thought about it :thumbup:smkdwnn said:10 min sounds good, glad i had u think about it!
make sure u put a new gasket
I didnt replace the gasket. The parts place by me is closed today, and besides the old one came off cleanly with the egr and I tested for leaks.......all is good
That egr crust covering the hole in the manifold is the only type of EGR problem I found associated with NOx failures on the Camry. Like you, I found the gasket survived the process with no sweat. After the third such experience, I gave up on sucking on the hose and went to "fix it and ship it."
Speaking of ford products, we would often get a check engine light for (I think) a code 33, and that usually meant replacing the EVP (egr valve position) sensor. The alternative was cleaning the EGR valve and/or filing some metal off the end of the sensor's metal shaft that rode on top of the EGR diaphragm. The valves could fail as well, which meant having a huge snap-on angle-head wrench (1-1/14 inch) for all of the E-vans that failed a test or suffered a bad valve.
My dad owned a Corona in 1971, and that was the first Toyota product I worked on. They have improved tremendously over the past 30+ years, and taught us a lot about quality and innovation. Mr. Toyoda can thank us for sending Mr. Deming to Tokyo and teaching the Japanese how to become a major economic force in automobiles and electronics. JVC stands for the "Japanese Victor Company," an RCA offshoot.
If I could make one suggestion to Toyota, it would be to make the service manuals better, both in wording and in diagrams. Reading a Toyota schematic is a skill that differs from standard electronic or automotive conventions, and the sentence structure used int he service descriptions is often a little obtuse.
Perhaps this persists because we are "gygin" (pronounced "guy-jzeen").
Speaking of ford products, we would often get a check engine light for (I think) a code 33, and that usually meant replacing the EVP (egr valve position) sensor. The alternative was cleaning the EGR valve and/or filing some metal off the end of the sensor's metal shaft that rode on top of the EGR diaphragm. The valves could fail as well, which meant having a huge snap-on angle-head wrench (1-1/14 inch) for all of the E-vans that failed a test or suffered a bad valve.
My dad owned a Corona in 1971, and that was the first Toyota product I worked on. They have improved tremendously over the past 30+ years, and taught us a lot about quality and innovation. Mr. Toyoda can thank us for sending Mr. Deming to Tokyo and teaching the Japanese how to become a major economic force in automobiles and electronics. JVC stands for the "Japanese Victor Company," an RCA offshoot.
If I could make one suggestion to Toyota, it would be to make the service manuals better, both in wording and in diagrams. Reading a Toyota schematic is a skill that differs from standard electronic or automotive conventions, and the sentence structure used int he service descriptions is often a little obtuse.
Perhaps this persists because we are "gygin" (pronounced "guy-jzeen").
i couldn't remove the egr valve today, i turn the 2 nuts connecting the egr to the manifold they turned and came off but the bolt stays. The egr won't come off.
The studs are supposed to stay in the intake manifold. The two nuts come off the studs, and if you wiggle the valve for a few seconds it will let go of the gasket and come off.
Then, slide the valve off the studs, clean the opening in the manifold, and slide the valve back onto the studs. Tighten up the nuts and you're done.
On occaision, I have taken a small plastic hammer and gently tapped on the more stubborn EGR valves to make them part with that gasket.
Then, slide the valve off the studs, clean the opening in the manifold, and slide the valve back onto the studs. Tighten up the nuts and you're done.
On occaision, I have taken a small plastic hammer and gently tapped on the more stubborn EGR valves to make them part with that gasket.
watch leaving hunks of carbon in the intake, the piston might not like them
I used to be concerend about hunks of carbon, but I have found that the many injector/intake valve/combustion chamber/intake manifold/ EGR cleanings I have done never revealed a problem with pistons crunching carbon.
I once had an Escort 1.9L come in with a loud tapping sound. The steel valve insert that acts as a valve seat had cracked and fallen into the cylinder. That's the kind of thing guaranteed to be a problem.
The carbon seems okay, though.
I once had an Escort 1.9L come in with a loud tapping sound. The steel valve insert that acts as a valve seat had cracked and fallen into the cylinder. That's the kind of thing guaranteed to be a problem.
The carbon seems okay, though.
Since I cleaned out my EGR, Ive noticed a nice-sized jump in my MPG!
Lol Fords :lol: . Fords = Champion of weird and costly designed-in failures. No wonder they are going belly up!I once had an Escort 1.9L come in with a loud tapping sound. The steel valve insert that acts as a valve seat had cracked and fallen into the cylinder. That's the kind of thing guaranteed to be a problem.
I'm sure a lot of Fords put mechanic's kids through college. With the TFI ignition module and inertia switch problems, the 3.8 L head gaskets, the CFI idle actuators, the fuel pumps....man, if they "had a better idea," they haven't mentioned it.
Of course, we had a lot of characteristic repairs at Toyota, as well. The 22RE had a nasty problem with the rocker shaft, making for an almost diesel-like valve noise, and the Gen 2's had a recall on the power door lock relay. Still there is a great difference bewteen a workforce that has come to expect entitlements vs a workforce that worries that their performace may dishonor their ancestors.
But what do I know. I'm just a gygin.
Of course, we had a lot of characteristic repairs at Toyota, as well. The 22RE had a nasty problem with the rocker shaft, making for an almost diesel-like valve noise, and the Gen 2's had a recall on the power door lock relay. Still there is a great difference bewteen a workforce that has come to expect entitlements vs a workforce that worries that their performace may dishonor their ancestors.
But what do I know. I'm just a gygin.
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