Don't ask me where I got this bad EGR from a 2006 CRD with 3000 miles. All I can say is that I spent A LOT of time bartering.

The EGR can be broken down into two parts, the solenoid on the right and the EGR valve on the left.
The EGR on the CRD is an electrically controlled EGR. There is some mis-information out there that the EGR is vaccum operated and modifying the exhaust will void the warranty. That’s pure horse hockey!
There are two small coolant pipes for coolant in and coolant out, which cool the two mated surfaces between the solenoid and EGR. The solenoid would get burned up in a hurry if that coolant jacked did not act as a heat sink.
This is yet another load on the coolant system along with the engine and transmission cooling needs. It’s imperative to have a good operating cooling system. Make sure that you take good care of doing your radiator flush and fills each year.


Rotational View.
This shows the inlet for the exhaust gases to come in.


Rotational view.
This shows the cavity where the cooled exhaust gases mix with the CAC (Fresh Air) coming from the output of the intercooler and passing through the EGR Flow Control Valve


Rotational view.


Rotational view


The solenoid is on the left and the EGR valve is on the right. Notice how the surfaces mate with each other. The solenoid basically either pushes or retracts the pintle against the seat of the EGR which causes the EGR valve to open.
Also, notice that the solenoid can "sense" if the EGR valve is closed because the seat of the outer ring EGR contact plate will seat flush against the solenoid.


This is another closeup showing the solenoid and the pintle.


This shows that without a current applied to the solenoid, I can use a pencil to push it down. It acts similarly to a dead bolt on a door. It's either retracted (pulled in ) or extended (pushed out). If the pintle is pushed out under a current applied to the solenoid, forget using a pencil to move it.

This is a close up of the EGR surface that mates to the solenoid. Notice that there is a stripe on the left of the surface. This could be a leak from the coolant jacket.


This is a side view of the EGR there are two diaphram disc valves on each side of the spindle. If the EGR is closed then no gases are in the cavity. This cavity is where the CAC air (Fresh Air) comes from the intercooler and is controlled by the EGR Flow Control Valve. The Flow Control Valve is not pictured.


Another view of the EGR where you may see the disc valve barely.


This is where the exhaust gases enter to be recirculated in the previous picture


To push the EGR Valves in the open position, takes quite a bit of pressure by the pintle from the solenoid. I'm using a screw driver here to show that the spring always holds the valves shut so that no exhaust gases enter.


I really had to push HARD with my thumb on the EGR plate to force the diaphram discs to open up. You'll notice that this opens the valve for the exhaust gases to come into the larger EGR cavity to be mixed with the fresh air. The exhaust gases them mix with the CAC (Fresh Air).


This shows that the cooled exhaust gases are now let into the EGR cavity to next be mixed with the CAC (Fresh Air) and then be pushed into the intake.


I'm sure these photos will stir much discussion, which I hope they do.

The failure points for the EGR as far as I can tell are the following:
1) The solenoid fails and does not operate the pintle in and out.
2) The Coolant Jacket fails and leaks
3) The EGR diaphragm valves get stuck and the solenoid cannot operate

Keep in mind that the EGR pictured above and the EGR Flow Control Valve will throw the same CEL value. Many times the techs will replace both but the flow control valve is much easier to remove and replace. It can be done from topside quickly. Therefore under warranty the tech will do that quickly as it pays better.
Removing the EGR is not a quick component swap.

_________________
2005 Black CRD Limited w/105,000 miles
Mann Provent 200, Airbox Mod, ORM Mod
New 545RFE, TC & Redesigned pump @ 25,020 miles
New EGR Flow Control Valve @ 25,020 miles
New Transfer Case input/output seals @ 32,787 miles
SEGR Kit @ 52,000 miles
SunCoast TC and Transgo Shift Kit @ 52,000 miles

DZL LOU,

Thanks for taking the time to take these pictures and post them etc.

_________________
Matt B.

05 Limited CRD. Bought it new. 112k on the clock now.

GDE Eco-tune, rear differential drain plug (drilled and tapped the pumpkin), transmission pan drain plug, Fumoto oil valve, fuel filler neck restriction removed, front hitch, Hayden fan clutch, Sears P1 battery since 08, Mobil 1 5w40, 5 volt glow plugs, DIY timing belt at 109k

DZL_LOU

Thanks for taking the time to share this information. It appears from your pictures that the VW TDI egr valve (from pictures on TDI club.com) is much larger than the CRD egr valve. The egr valve (the actual valve itself, not the outside assembly, you show looks to be 1/2 the size of what VW uses on a 1.9 or 2.0 liter diesel engine. Can't help but wonder if the small size is the reason for clogging so quickly. Maybe OldNavy can comment on the relative size since he may have had a TDI egr valve apart.

_________________
2005 LTD CRD RB1 NAV/Htd Leather seats/Amsoil EA filters
SunCoast Mega Trans & Billet TC/PML pan/Aux cooler
Fuel cooler/Lift Pump/10um Pri/Racor R490 2um Sec Fuel Filters
IronMan Lift/Shocks/Provent/Moog ball joints/ V6 Airbox/Fan/Hayden
Cobalt Boost/EGT/Oil/Trans/Volt gauges/Aeroturbine 2525
Yeti Hot Tune/Odessey 65/Samco's/Michelin Defenders

I would hope it's the solenoid that is going bad as the valve itself looks pretty robust. So this is the thing causing all of us so much grief??? Doesn't look so scary now. Good job with the disection!

_________________
'05 CRD Sport born on 06/20/05, bought on 9/23/05, L.O.S.T. on 9/27/05 - modding ever since:

Daystar 2.0" Lift, P255/70R16 Revos, Boulder Bars, Reese Front Hitch w/9k Hooks, Poison Spyder Rock Ring, MOPAR Skids/Bug Shield/Roof Rails/Mats, WARN Hitch Shackle(Rear), 10k Hitch Hook(Front), Custom Tilt/Slope Meter, Ammo Box Mod, Rotella T 5W-40.

Thanks for the pics!

I wish I was more tech-savy so that I understood better what it was all about...

Anybody want to draw some "pictures" on top of the photos to show which direction the exhaust, cold air and mixed stuff are flowing in???

Thanks again, even if I'm a bit tarded...

_________________
Yours Truly,

Special Agent

Warning, bitter rant about EGR's follows:

People have been wondering what these things do since they started putting EGR's in engines. The answer is simple: the EGR serves no usefull purpose except to reduce engine emissions at the expense of fuel economy, horsepower, and engine life. EGR's work by taking some of the exhaust from your engine and feeding it back into the engine's air intake to get "burned" better (less particulate emissions being the desired goal). It is kinda like eating your own feces to try and build up an immunity to the e. colli in the Spinach salad. It is just a bad idea. A superheated section of the exhaust that burns exhaust particles more completely would be a better idea. So would urea injection, which causes a chemical reaction that reduces emissions. But, thanks to pencil pushers at the EPA and elsewhere, as well as the bean counters at the automobile companies-- we don't always get technology that solves real problems.

The EGR steals your horsepower by putting hot exhaust gasses into the combustion chamber (which take the place of clean colder air which is more dense in oxygen). It can also steal more horsepower, depending on design, by interrupting the flow of the engine exhaust, which creates backpressure that must be overcome by the engine. EGR's reduce engine life by putting dirty soot into the intake of your engine (some of your exhaust is going back into the combustion chamber to give those moving metal parts something to grind against, not good!). It reduces fuel economy as a direct result of all of the proceeding (increased engine wear and robbed horsepower).

Since it is an emissions component, is illegal to remove or tamper with. So we are basically doomed to spend 600 bucks after the warranty ends every 18,000 miles for the rest of the vehicles existance. That is, unless ULSD (Ultra Low Sulfur Diesel) fixes the failures that are occuring with the EGR's. The theory is that ULSD has less sulfur... which means it has less emissions when burned, which in turn means the EGR valve does not have to work as hard. It is hard to know for sure if the ULSD will improve the failure rate unless we know why these are failing in the first place. The plugging up seems like a reasonable guess for failure, and would mean that ULSD should help the longevity. Leaking seals and faulty sensors are more ominous-- I can't see how ULSD is going to help either of those. Perhaps the plugging is causing the other two by generating too much heat.

And there you have my bitter EGR rant.

Pablo, that spinach thing...very funny

So this valve is a simple open and shut valve, correct? And the EGR Flow Control Valve (fcv) is what modulates how much flows correct? So if we just take this solenoid off so that it can move freely, put a plate over where it mounts, (or just use a disconnected solenoid) Will the system know the difference?

_________________
It may be that your only purpose in life is to serve as a warning to others.

06 CRD Sport
Built 5/11/06
Jeep Green
Rocklizard diff cover
V6 Airbox

I suspect it works like the Bosch systems on the VW tdi's. That is when the EGR is opened the maf sensor senses a drop in volume of airflow and knows the egr is working. No change gives a cel. Some have been known to rig a vacume operated switch, resister and diode to fool the computer when the EGR is unhooked by changing the maf values:lol: This would not work on our CRD's because the valve is operated electrically instead of vacume like the vw's Also vw does not have a flow control valve but just a "anti shudder" used on shutdown.

_________________
Atlantic Blue 06 CRD Limited (his)
Joined by a 2000 XJ Classic (hers)

Pablo, I agree with everything you said except for a few sentences. The EGR is due to our beloved EPA , but without the EGR we would have not been able to purchase the CRD in the USA.

Here's where I disagree.
1) The EGR steals 5%~8% of MPG by being installed, and the corresponding HP that goes with that reduction.

2) Not pictured in my post was the EGR Cooler. This is a another coolant jacket that actually REDUCES exhaust gas temperature by several hundred degrees before it is mixed with CAC air and introduced into the intake. This is to LOWER the combustion chamber and cylinder head temp.

3) When compared to exhaust gases, the oil in the from the CCV coming through the CAC is the big contributor to the soot.
I do agree there is soot in the exhaust gases as you can see from pictures, but mixed with oil from CAC just makes it worse.

_________________
2005 Black CRD Limited w/105,000 miles
Mann Provent 200, Airbox Mod, ORM Mod
New 545RFE, TC & Redesigned pump @ 25,020 miles
New EGR Flow Control Valve @ 25,020 miles
New Transfer Case input/output seals @ 32,787 miles
SEGR Kit @ 52,000 miles
SunCoast TC and Transgo Shift Kit @ 52,000 miles

Yes, It's just a valve to be either open or shut in the mode of operation. Before disassembly, I thought it had degrees of being open.

As for getting rid of it, I'd keep the solenoid operational but other considerations are then you need remove the EGR and to plug the the small exhaust feed and plug where the EGR mounts to.

_________________
2005 Black CRD Limited w/105,000 miles
Mann Provent 200, Airbox Mod, ORM Mod
New 545RFE, TC & Redesigned pump @ 25,020 miles
New EGR Flow Control Valve @ 25,020 miles
New Transfer Case input/output seals @ 32,787 miles
SEGR Kit @ 52,000 miles
SunCoast TC and Transgo Shift Kit @ 52,000 miles

From what I can tell, exhaust gases flow into the round orifice. If the EGR valve is open, then those exhaust gases are released to the space occupied by the rectangular orifice where they go to meet the fresh air (CAC) from the intercooler.
After the exhaust gases and air from intercooler meet they have left the EGR and are on their way to the intake.

So basically, the EGR pictured is a exhaust gas "traffic cop" allowing the exhaust gases to come in or stopping them from coming in.

_________________
2005 Black CRD Limited w/105,000 miles
Mann Provent 200, Airbox Mod, ORM Mod
New 545RFE, TC & Redesigned pump @ 25,020 miles
New EGR Flow Control Valve @ 25,020 miles
New Transfer Case input/output seals @ 32,787 miles
SEGR Kit @ 52,000 miles
SunCoast TC and Transgo Shift Kit @ 52,000 miles

I used to think blow-by oil was the primary cause of egr failure also - that's why I installed a Provent on my CRD in April 2005. However, 2 replacement egr's later, I'm convinced that in spite of running a lot of B20 and PS in every tankful, the sooty exhaust being recirculated back into the intake system is definitely the major contributor to the problem. The CAC oil will accelerate this issue, but from my experience, when removed, does not eliminate it. A study consiting of a single sample

My first egr failed due to carbon buildup according to the tech who removed it, at 8K miles and the provent had been on for 5.5K miles, with only 2500 miles without it. The carbon was much harder looking than the buildup on the valve in your pictures. It may be that in the hot summer weather in the southeast, the soot carbonizes on the egr valve areas faster than it would otherwise - similar to a cake slowly burning in the oven when left in too long at too high a temperature. The extra heat load on the cooling system from egr is estimated to be as much as 40% according to some estimates I've seen - this will result in more heat load for longer periods of time, exacerbating the heat buildup in exhaust temperatures, further causing carbonizing of the soot in the egr chamber.

I would be interested in seeing how many "long life" egr valves, those with 25Kmiles or more without failure, run in colder or moderate climates in the northeast or western northern states. This is inspired by a long study published on tdiclub, where certain tdi owners worked in companies with access to scientific equipment capable of anaylsis for early failure of MAF sensors. His final analysis, was that defective solid state design of the heater element on the MAF, exacerbated by cold temperatures of northeastern states, Mass, Conn, N.H. etc, caused the heater to run longer duty cycles and expose the weakness of the design. His findings were based on TDI owners sending in their failed MAF sensors to him from all over the US and he noted that the repeated MAF sensor failures were from owners in northeastern states. That's why I'm wondering if CRD owners with multiple egr failure have something in common, i.e. long idle times, hot climate, predominately highway miles driven, long traffic light times or any condition which would cause the egr to cycle on longer, heat the soot in the valve chamber for longer than average.

On my CRD, the 2nd egr failed at 12K, full provent protected miles later(20K odometer miles). Again, according to the tech, it wasn't electrical failure, but carbon buildup on the valve that caused it to go bad. For all I know, the egr valve might be sold separately from the solenoid - it's possible that I'm still running the orignal solenoid. So while the provent has been a tremendously worthwhile investment to keep blowby oil, which we know to be somewhat excessive, out of the egr and intake system, it alone cannot prevent failure of what I believe to be a inadequate lifecycle egr design.

After seeing your pictures, I'm now even more convinced that the egr valving size, in comparison to the TDI closeup pictures I've seen, is insufficient to handle the amount of soot buildup and eventual carbonizing that occurs. It could also be inadequate design of the shaft that this valve seat runs on causing sticking. The carbonizing I'm referring to is a result of the agressive cycling that prev 07 EPA emissions required of this system. You can infer that current egr technology was at it limits of effectiveness by the fact that it couldn't meet the even more stringent 07 and 09 EPA diesel emissions requirements - hence the SCR and plasma systems being designed for newer diesel engines. Being at its limits can also infer that our egr designs are cycling the maximum egr gas into the engine that it can handle and still run - further supporting the idea that excessive carbon buildup is repsonsible for failure of these systems.

If solenoid failure were the cause, I don't believe the TSB would list the actual valve itself on the replacement parts list. Also, on my first egr replacement, the tech told me that Star required a battery of photographs of the carbon buildup within the valve to be sent to them before they would release the replacement part. This speaks to unexpected failure modes, probably due to direct lack of experience of repair on such a high duty cycle of egr gas and soot traversing the valve system. Industry research with paying owners contributing down time under warranty to the knowledge base.

While the EPA emissions doesn't require a certain amount of oxygen deprived exhaust gas to be injected into the intake of the engine, their absurd NOX reduction requires lowering of the burn temperature from optimum for any diesel engine to lower NOx output. This is where the performance loss that Pablo speaks of is coming from. For longer term results, we have not even begun to experience the results of the grit from egr being reintroduced into the cylinders over hundreds of thousands of miles yet. Most original owners will not have the vehicle when this effect shows up.

The cooler you speak of is quite large in comparison the egr valve itself - I'm now wondering if it isn't slowly clogging up due to the small passage sizes the soot must flow through before exiting into the intake system on the engine.

To put a common sense big picture perspective on all of the grief this system is causing owners everwhere - the egr is there primarily to reduce NOx emissions by a miniscule amount (not precentage but actual grams) from 04 standards - for a theory that the EPA cannot conclusively prove to the satisfaction of scientists that NOx is the major reason for smog creation - with real world evidence every weekend in California refuting the EPA position on NOx to smog creation. An abuse of regulatory authority that is costing citizens paying the salaries of these EPA faschists hundreds of millions of dollars annually due to restriction of diesel powered fuel effecient vehcile availability in the marketplace.

Further, it is now believed by some scientists that smog is actually going to increase as a result of NOx reduction - if that turns out to be the case, the entire EPA leadership should be terminated, with pressure on our legislatures to replace them with objective EPA leadership who can use their authority for solving problems instead of pursing personal agendas.

Again, thanks for the pictures. I see its a Pierberg unit rather than a Bosch.

_________________
2005 LTD CRD RB1 NAV/Htd Leather seats/Amsoil EA filters
SunCoast Mega Trans & Billet TC/PML pan/Aux cooler
Fuel cooler/Lift Pump/10um Pri/Racor R490 2um Sec Fuel Filters
IronMan Lift/Shocks/Provent/Moog ball joints/ V6 Airbox/Fan/Hayden
Cobalt Boost/EGT/Oil/Trans/Volt gauges/Aeroturbine 2525
Yeti Hot Tune/Odessey 65/Samco's/Michelin Defenders

What I keep coming back to is simply this:

We should come up with a way to permanently disable this "feature". I'd love to do it now, at 7K miles, than wait until it damages my engine. I bought a new vehicle that was a diesel with the belief that, not only could I run bio, but that I could keep it running for 200,000+ miles AT LEAST.

What's the "crime" you would be charged with again?

I'd be willing, with some techie experts from this board, to fight any legal action. We are obviously not helping the environment by ruining our engine's performance.

Could we get around it by installing urea injectors and then remove the EGR????

_________________
Yours Truly,

Special Agent

SpecialAgent,

Disabling the EGR is not difficult in itself. Options include:

Unplugging it.
Removing the solenoid.
Removing the entire valve and installing a blank plate in its place.
Installing a plate over the port where exhaust gas enters.

All these will disable the EGR, but it will result in a Check Engine Light.

Disabling the EGR without a resulting Check Engine Light is more difficult. Possibilities:

Modify the software to not use the EGR or not look for it.

Substitute a separate filtered fresh air supply for the exhaust gas.

Install a device which would fool the computer by changing the air flow signal to the required range whenever the EGR valve is switch on. This could be as simple as a relay which would switch in a resistor and drop the voltage of the the air flow signal to the computer. Note the use of the phrase "could be as simple as." I'd like to have back all the time I've spent on "simple" things that really weren't.

_________________
Matt B.

05 Limited CRD. Bought it new. 112k on the clock now.

GDE Eco-tune, rear differential drain plug (drilled and tapped the pumpkin), transmission pan drain plug, Fumoto oil valve, fuel filler neck restriction removed, front hitch, Hayden fan clutch, Sears P1 battery since 08, Mobil 1 5w40, 5 volt glow plugs, DIY timing belt at 109k

This is an approach doomed to failure - to fight emission laws (admittedly bad science laws) puts you on the wrong side of the issue. Time better spent contacting legislatures on the policies of the EPA not warranted by careful, sound reasoning and real world experience. Changing bad emissions law and policy would benefit many more, instead of a few diesel owners capable of defeating egr controls.

The egr can be defeated in theory at least. However, defeating egr controls, if it works, only benefits a few who can modify their systems to do it. A much, much better approach is work to change the bad policy EPA emissions law. Nice thing about legislatures being elected - if they received enough input from voters, they eventually start to act out of a sense of self preservation - in this case, putting pressure on the EPA to retool their managment team with problem solvers rather than politicians.

_________________
2005 LTD CRD RB1 NAV/Htd Leather seats/Amsoil EA filters
SunCoast Mega Trans & Billet TC/PML pan/Aux cooler
Fuel cooler/Lift Pump/10um Pri/Racor R490 2um Sec Fuel Filters
IronMan Lift/Shocks/Provent/Moog ball joints/ V6 Airbox/Fan/Hayden
Cobalt Boost/EGT/Oil/Trans/Volt gauges/Aeroturbine 2525
Yeti Hot Tune/Odessey 65/Samco's/Michelin Defenders

isabling the EGR is not difficult in itself. Options include:

Unplugging it.
Removing the solenoid.
Removing the entire valve and installing a blank plate in its place.
Installing a plate over the port where exhaust gas enters.
possibly at the exhaust manifold on the passenger side, where the pipe from the egr valve connects.

All these will disable the EGR, but it will result in a Check Engine Light.
Disabling the EGR without a resulting Check Engine Light is more difficult. Possibilities:

Modify the software to not use the EGR or not look for it.

Substitute a separate filtered fresh air supply for the exhaust gas.
Possibly by disconnecting the egr pipe from the exhaust manifold to the egr input flange, substituting instead a pipe connected to a small circular filter. This fresh air supply access is controlled by the egr valve, only works when the egr is turned on and prevents turbo boost from escaping, as the turbo boost is deactivated by the ECM whenever the egr is turned on. This might even prevent a MIL light, as the MAF still records a reduction in air flow because the afc valve still restricts fresh air flow from the filter box, where the MAF resides, while the new air source, connected to the egr intake port, supplies fresh filtered air instead of exhaust gas. It also guarentees a stiff EPA fine of several thousand dollars if emissions checks discovers this modification. This is why its better to change bad laws instead of violating them, even for good reasons.

Install a device which would fool the computer by changing the air flow signal to the required range whenever the EGR valve is switch on. This could be as simple as a relay which would switch in a resistor and drop the voltage of the the air flow signal to the computer. Note the use of the phrase "could be as simple as." Wink I'd like to have back all the time I've spent on "simple" things that really weren't.

_________________
2005 LTD CRD RB1 NAV/Htd Leather seats/Amsoil EA filters
SunCoast Mega Trans & Billet TC/PML pan/Aux cooler
Fuel cooler/Lift Pump/10um Pri/Racor R490 2um Sec Fuel Filters
IronMan Lift/Shocks/Provent/Moog ball joints/ V6 Airbox/Fan/Hayden
Cobalt Boost/EGT/Oil/Trans/Volt gauges/Aeroturbine 2525
Yeti Hot Tune/Odessey 65/Samco's/Michelin Defenders

Yes, the pictured EGR was from a 2006 CRD with 3K miles. The source who gave me the EGR dismissed the failure to the use of BioDiesel. I have absolutely no opinion on this because the evidence is simply not there to substantiate it.



OldNavy's thread "Crap.... P0401 EGR" started to collect that type of info further in the thread, but I think a new thread with this specific type of info you mention is the first step in collecting our imperical data as to the environment and driving habits.



IMHO, the solenoid is operationally simple and assuming it's not defective from factory, its' robust unless the heat sink cooling jacket did not do it's job between the solenoid and the EGR.
DCX sells the EGR and Solenoid as one unit bolted together. I separated the two for purposes of illustrating the dissection pictures.



Yes I agree. Now add to that fuel that combusts at a lower temp along with the exhaust gas and that adds more to list of incompletely burned byproducts once again only to get recirculated.


Yes, thats true here is a picture of the EGR Cooler with the cooler lines on top. Since I can't see the whole component 360 degrees, I can't tell if the opening to the left is the exhaust gas inlet or outlet




Can't agree more. How about we figure out what is causing these to fail, and then how to either fix it or out smart it?

_________________
2005 Black CRD Limited w/105,000 miles
Mann Provent 200, Airbox Mod, ORM Mod
New 545RFE, TC & Redesigned pump @ 25,020 miles
New EGR Flow Control Valve @ 25,020 miles
New Transfer Case input/output seals @ 32,787 miles
SEGR Kit @ 52,000 miles
SunCoast TC and Transgo Shift Kit @ 52,000 miles

_________________
2005 LTD CRD RB1 NAV/Htd Leather seats/Amsoil EA filters
SunCoast Mega Trans & Billet TC/PML pan/Aux cooler
Fuel cooler/Lift Pump/10um Pri/Racor R490 2um Sec Fuel Filters
IronMan Lift/Shocks/Provent/Moog ball joints/ V6 Airbox/Fan/Hayden
Cobalt Boost/EGT/Oil/Trans/Volt gauges/Aeroturbine 2525
Yeti Hot Tune/Odessey 65/Samco's/Michelin Defenders

Without enough data collected to detect a trend or pattern within all of the failed egr valves, we could experiement, via Internet communication, with yours... for example. we know from owners with egr temp gauges what some commond CRD exhaust temperatures are while idling, cruising at 60-75 mph and on cooldown. Iirc, on a CRD at operating temperature, these are ~ 450 - 650F on idle, 750-950 on highway driving and I believe the max I can recall is about 1100F at WOT.

So, if you can rig a thermometer up on your egr valve and supply a heat source of 450F - 650F to the sooty area of the egr valve itself, would it be possible to see what that soot looks like once heated for 10, 20 or even 30 hours of 500F temperatures? Minus the solenoid of course. Maybe a kiln oven that ceramics are baked in would do - no external thermometer needed if that's available. I would be tempted to put it in the oven for a 10 hour period, but I know what my wifes reaction would be - so I wouldn't dare suggest that

Something that could be temperature controlled to a specific heat, over a period of time, unattended in ones garage, safely, to monitor the carbonizing of soft soot particles into hard carbon? Or could the failure be traced to improper expansion rates of the valve guide within the seemingly soft aluminum housing - i.e. different expansion rates for steel and aluminum? Or does the egr chamber have a steel guide that the egr valve shaft slide within, similar to engine head valve guides? Some possible ideas to try to produce a failure mode with heating conditions similar to real world. We obviously don't have a continuous soot supply source for testing.

I don't really think biodiesel is the cause of egr failure - too many CRD owners who have never used or had access to bio with failed egrs. In fact, the studies I've seen show significantly less particulate formation with bio than with D2. You would think these egrs would last longer with bio than without it, under identical driving conditions, if soot formation is the failure cause.

Another idea - can this egr valve be cleaned and returned to operating condition? I ask because a friend with a CRD had the egr go at 10K miles, all on D2. The techs cleaned his egr valve and returned it to service - no replacement - he was furious and traded it in because they kept if for 10 days to perform that operation, gave him a very difficult time concerning a rental while it was in the shop. When it was returned, it had not a single flash tsb performed, which he had requested. A few days later his transmission started leaking oil. Yes, it was a 5 horned dealership by the great lake of Norman.

_________________
2005 LTD CRD RB1 NAV/Htd Leather seats/Amsoil EA filters
SunCoast Mega Trans & Billet TC/PML pan/Aux cooler
Fuel cooler/Lift Pump/10um Pri/Racor R490 2um Sec Fuel Filters
IronMan Lift/Shocks/Provent/Moog ball joints/ V6 Airbox/Fan/Hayden
Cobalt Boost/EGT/Oil/Trans/Volt gauges/Aeroturbine 2525
Yeti Hot Tune/Odessey 65/Samco's/Michelin Defenders

I own a CRD, I hate the EGR vavle problems. But dont blame this on the EPA. I could hear everyone bitching about the EPA if we all lived next to a toxic waste dump, or if you lived somewhere like Pittsburgh, PA in the early 1900s where pollution was so bad you could barely see the sun. Without some kind of emmission controls, there would be more respiratory health problems in the US, so just be glad that the underappreciated people at the EPA are out there protecting you. Would you all like to go back to the 60's, where everyone was spewing lead into the air with each fillup? I also would like to find a solution, but I think that falls on the shoulders of our auto manufacturers coming up with systems and parts that dont crap out every 18,ooo miles.