EGR valve modification to help in carbon removal. Carbon filter basket installed.

[Kernal]

Note: added topic of an EGR valve mod to original thread beginning
at post #5:

I've been wondering if it would it be possible to retrofit an EGR particulate filter ie: somewhere between the EGR pipe and the EGR valve possibly? Seems like some vehicles (? VW and some diesels) have those from the factory. They do require maintenance but they're designed for that.

Something to prevent soot from getting into and past the EGR valve then into the intake and sucked into the engine making a mess and plugging things up as it goes.

So what options might there be: a sintered brass plug (removable for cleaning) in the EGR pipe? Stainless steel mesh?? Carbon fiber infused ceramic nanotubes??

The ultimate cure would of course be to delete the EGR system altogether but that's not an option for people who live in states with Emissions testing.

Just brainstorming here.

Any positive thoughts out there?






@NLXTACY





@landtank

Edited: added EGR valve modification to the title and photos

 

[baldilocks]

The egr tube is in such an inaccessible place that packing up and moving somewhere else sounds easier. Honestly.

 

[Malleus]

If you were going teh retrofit route anyway, why not cut the tube and weld in a fitting, or two, so you could swap in/out a filter?

 

[Kernal]

That was one idea/thought that came to mind, don't have the welding equipment/skills however.

One other thought; tap the intake plenum just after the EGR valve and EGR temp sensor (or at the temp sensor port and re-position the temp sensor) then route the gases via a low profile pipe-filter-pipe to further down the EGR passageway to were it dumps in just downstream of the Throttle Body??

That might provide more space for a filter, and for servicing the filter??

 

[Kernal]

Bringing this back instead of starting a new thread. Edited for accuracy/clarity.

So I had a new OEM EGR valve modified, I specifically asked a machinist to tap the EGR valve casting for an M8 threaded plug.

Backstory: the factory EGR casting for 95-97 FZJ80 US spec models has a protrusion or hump whereas in the 93-94 FZJ80 US spec models there's already a threaded hole (for EGR temp sensor?) at that location.

As I already had a new 95-97 EGR valve sitting on the shelf instead of
buying the earlier part I just had the later EGR valve taped for a M8 threaded plug that is available for that purpose from Toyota.

Either way, the purpose of tapping the EGR valve for a new port is for direct access to the upper chamber than can get clogged with soot/carbon. (if your EGR valve already has that port you're good already).

So every few months the idea is to remove the M8 plug in the EGR valve spray in some ? GDI cleaner, Throttle Body cleaner etc, into that port to hopefully clean out some of the carbon then replace the M8 plug.

With models that have an EGR temp sensor on the upper intake plenum there is an almost straight through path from that temp sensor port through to the EGR valve (top chamber, see photos).

And by removing both the EGR Temp sensor and the new plug then cleaner could be sprayed from the Temp sensor port (intake side) directly into and through the top chamber of the EGR valve (to blow the carbon out of the system instead of downstream toward the TB).

That's the theory at least.


Top photo: new M8 threaded hole/port; note it lines up with the exit port
of the valve going into the intake plenum: If you magnify the photo (click twice) you can see some of the pintle valve/shaft.

Middle Photo: note new M8 plug, the threads on this plug are not the same as the EGR temp sensor plug (?BSP or BSPT). This begs the question,
is there a different model that uses this same EGR valve but which
has that port already tapped ie: what's the purpose of the hump/bump
on the EGR valve at that location?? Is/was it used for an EGR temp sensor
on a different model?? Also note the threaded blind hole to the right, that's for the bolt (different threads) which attaches the EGR vacuum modulator bracket.

Bottom photo: note again the almost straight through path looking from
the intake plenum side toward the new port:

 

[Kernal]

Finally found the time to get the new EGR valve installed. Was unable to find any sort of actual soot filter that could be retrofitted but did find a thimble size screen/basket that would fit inside lower EGR inlet port where it bolts up to the EGR pipe.

Theory is that any large chunks should be stopped by the screen and then should break up with heat. Every few months a GDI type (high PEA content) intake valve cleaner could be sprayed into the lower part of the EGR valve via the pipe for the vacuum modulator (remove hose, spray in cleaner, let soak, run engine with hose disconnected, reconnected hose).

The top chamber of the EGR valve could be cleaned out by removing the EGR temp sensor and M8 plug then spraying GDI cleaner (to remove carbon) straight through from one side to the other.


Photos below:

Note filter basket (actually two, one on top of the other turned 90 degrees due to the large mesh size) stuffed into the bottom port of the EGR valve before attaching to EGR pipe. The photo may make it look like the screen is blocking flow but there's plenty of space between the mesh for the exhaust gas to flow through.

So will the mesh filter basket do anything?? IDK, it obviously won't stop small soot particles. I'll let everyone know the results in 50,000-100,000 miles.


Double click on photo for close-up view of filter basket mesh:

Note in the photo below how the stud holes don't line up with EGR pipe nut screwed on before the studs were installed. Some people may be able to force the valve into place while installing the studs and gasket, I couldn't. So the large nut was backed off all the way then the studs, nuts, and gasket installed, the large pipe nut was tightened last (ie: the photo below is NOT the best way to do it)

Bottom photo shows the EGR valve reinstalled (actually haven't yet tightened the large nut, couldn't find my crescent wrench in the dark).

Note heat sleeve over the EGR pipe, this extends all the way down it's length. Once the large nut is tightened all the way the heat sleeve will be pulled up over the nut. Purpose is to decrease as much heat as possible to the engine harness (also re-wrapped with TESA tape then a heat sleeve):

FWIW I painted the EGR valve before installation with high heat engine primer and paint using a bunch of foam ear plugs to stuff all the holes while painting. I paid particular attention to the small vacuum pipes on the top rear of the valve as IME the right side pipe tends to rust out before anything else.

Trivia point: the white paint (Japanese letter?) seen on the intake plenum is, AFAIK, original to the vehicle (ie: someone at the factory put it there)

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Added an EGR valve R&R procedure to this thread as it's been a long time since I last installed an EGR valve in this engine and fought with it a bit until I relearned the procedure. For those that also have forgotten, here's the procedure I used:


Removing EGR valve (main points):

Large crescent wrench set to 1-1/4" worked IME to break the large EGR pipe nut free from the EGR valve, finish loosening with adjustable slide type wrench or whatever you have

12mm socket to remove stud nuts (studs often come out with the nut
so buy new studs and nuts along with a new gasket before you start)

If EGR valve is stuck give it a slight tap or two with a rubber or plastic mallet
to loosen

E-Torx (external Torx) #7 socket to remove/install OEM studs (5mm 1/4" drive 6 point socket may work also) if they didn't come out with the nuts

Reinstalling EGR valve:

Locate EGR valve onto the EGR pipe but do not attach large nut yet.

Install new studs with a new EGR valve gasket. Studs should bottom out snugly on the unthreaded section. Some people like to use copper antiseize on the studs (don't use aluminum flake antiseize on aluminum).

There are tabs on the gasket top and bottom that can be used to ensure the gasket hasn't fallen out of place by feeling around the edge of the gasket before tightening the studs and nuts

Once the EGR valve and gasket are hanging on the studs go back and screw the large pipe nut by hand as far as it will go. I add copper antiseize to those threads.

Tighten new stud nuts, use correct torque specs from the FSM if you prefer
but remember if you use antiseize you need to back off on the torque setting on your wrench. (I use antiseize and tighten until snug using a small ratchet)

Finish tightening the large EGR pipe nut. I used a Milwaukee adjustable slide type wrench for most of the way, finished with a 10" Crescent wrench. (IME open wrenches of that size (32mm, 1-1/4") are too long/bulky to work with in that space)

FWIW

Key words: EGR valve removal installation R&R replacement filter basket

 

[Kernal]

Added photos above of reinstallation of the modified EGR valve to include a filter basket stuffed into the lower EGR valve inlet (see post above):

 

[Kernal]

Here's the link to the filter basket and gasket:

http://www.tomco-inc.com/Catalog/c26-2000%20egr%20carbon%20filter.pdf

I ordered Tomco Ford Part # 2-1377 but decided not to install the gasket with the mesh, it needed to be modified and figured that the mesh screen at the EGR valve inlet should be enough to stop big chunks. Installed two of the filter baskets turned 90 degrees to each other which I stretched open a bit so they would fit snugly inside the lower EGR valve inlet (see photo above).