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EGR issue
http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?f=5&t=5185		 Page 1 of 2
Author:  greiswig [ Tue Jan 24, 2006 2:35 pm ]
Post subject:  EGR issue
Hi, all,

I've got almost 4000 miles on my '05, so maybe it's about due...

Anyway, I recently seem to have been losing mileage. No CEL appeared, but I decided to try an experiment anyway: I blocked off the EGR pipe where it joins the EGR valve. Based on one other person's experience on this list, I expected to only get P0401 from this.

When I went to read the codes, I also got P0299, though. I don't know whether this code came up before or after I blocked off the pipe. And a search through the archives reveals two different interpretations of this code: "unidentified Fuel & Air metering error," or else "turbo under boost."

Any idea which, if either of these is the correct interpretation? How about whether this code could be caused by my blocking off the EGR pipe? I've cleared the codes and will run it again like this and see if they come back, but...it would be nice to know whether I have a larger issue here.
Author:  greiswig [ Tue Jan 24, 2006 8:48 pm ]
Post subject: 
Okay, here's an update: I cleared the codes after seeing P0299 and P0401. Drove for a bit, and no CEL, but a code scan revealed that P0401 was there almost immediately after starting up. Cycle on/off, and CEL came on almost immediately. Code scan revealed P0401 again, but...
...no P0299. So I still don't know exactly what P0299 means, and whether it meant that my EGR was on its way out before I blocked off the EGR pipe. In either case, my mileage has gone up 2-3 mpg according to the overhead display.
Author:  Danno [ Tue Jan 24, 2006 9:38 pm ]
Post subject: 
299 is turbo underboost.. Those 2 codes are the ones we all get when the egr is about to or has gone bad.

Search around some old posts youll find all the info you need.
Author:  greiswig [ Tue Jan 24, 2006 10:22 pm ]
Post subject: 
Danno wrote:
299 is turbo underboost.. Those 2 codes are the ones we all get when the egr is about to or has gone bad.

Search around some old posts youll find all the info you need.


I did search, Danno..."Turbo underboost" is one of at least three similar interpretations for this code that I've seen. I realize that these are common to EGR failures. However, I didn't get the P0401 until *after* I had blocked off the EGR pipe (based on the fact that the CEL didn't come on). What my original questions were:
1. What is the *correct* interpretation of P0299
2. Is P0299 likely caused by blocking off the EGR pipe, or was it there before?
Author:  Ranger1 [ Tue Jan 24, 2006 10:24 pm ]
Post subject: 
How does it run without EGR gas?? Notice any smoother pickup, acceleration, better throttle response?

P0299, underboost, is what came with my EGR failure, as well as low flow P0401. This makes sense if the EGR valve sticks open or won't close properly, as turbo boost would leak out into the exhaust at some point. What is unusual is that you have that underboost condition with the path to the exhaust blocked off. Is there any chance your block plate is leaking boost, if the EGR valve is indeed not closing properly? Maybe some soapy water on the block plate connection and starting the engine would show if it is leaking?
Author:  greiswig [ Tue Jan 24, 2006 10:32 pm ]
Post subject: 
Ranger1 wrote:
How does it run without EGR gas?? Notice any smoother pickup, acceleration, better throttle response?

P0299, underboost, is what came with my EGR failure, as well as low flow P0401. This makes sense if the EGR valve sticks open or won't close properly, as turbo boost would leak out into the exhaust at some point. What is unusual is that you have that underboost condition with the path to the exhaust blocked off. Is there any chance your block plate is leaking boost, if the EGR valve is indeed not closing properly? Maybe some soapy water on the block plate connection and starting the engine would show if it is leaking?


Runs fine without EGR, better than it did before. More like I remember it running when new, but I can't say that it's better than that. As I said earlier, mileage increased, too. But the whole reason for blocking this off is that I'd seen my mileage decrease over time, and suspected the EGR even without a CEL. What I *failed* to do was to check the codes right before I blocked off the EGR pipe, but I'd guess that the P0299 was there at that point, and the P0401 was not. Since I blocked it off, the P0299 has not reappeared.

I'll see if I can get some soapy water on the pipe end within the next day or two, but like I said, I think the P0299 was there before I blocked it off.
Author:  Danno [ Tue Jan 24, 2006 11:11 pm ]
Post subject: 
p0299 turbo underboost is what my scantool reported and what Chryslers DRB Scanner scanned and confirmed by STAR.

The 299 code came and went for a while before all hell broke lose, the 401 stayed and wouldnt clear. I suspect its only a matter of time for ya.
My CRD ran great when I unplugged the EGR, couldnt believe how good it ran.

Take a trip to the dealer and see what they say.
Id think by now they would have a stockpile of EGRs waiting for you.
Author:  AZScout [ Tue Jan 24, 2006 11:34 pm ]
Post subject: 
I did an experiment a month or so back. With all the talk about the EGR failure, I went to Autozone and had them check my Jeep. It came up with the 401 code. This is without any cel. So I knew something was going on but because the cel didn't come on I didn't take it in to the dealer. About a month later, my cel came on. I took it into the dealer and this time I got the 401 and 299. They ordered the EGR which they say has still been on backorder for the last three weeks now. They also said I had an extremely dirty air filter. They changed my air filter, gave me a software update and reset everything. It's been fine so far but I think it is just a matter of time... Just wanted to thow this into the mix to see if it could contribute to our ongoing problem.

Dave
Author:  Ranger1 [ Tue Jan 24, 2006 11:52 pm ]
Post subject: 
"Since I blocked it off, the P0299 has not reappeared. "

This sounds consistent with a theoretical (because I don't know for sure :-) ) slightly open, but sticking EGR valve.... The P0401 should be there as the ECU definately knows when EGR flow is out of spec. The P0299 shouldn't be there if the path to the exhaust is blocked, I would think. At least if they are measuring intake pressure and setting a code if its below spec. I'm guessing here, but it sounds like your EGR valve is not sealing properly. When they took my old EGR out, it was pretty crusty with black carbon looking deposits. And that was with a lot of highway driving for 8K miles. So I would venture another guess that the EGR is sticking in a slightly open position, not providing enough EGR flow to satisfy the ECU expected parameters, and open enough to bleed down turbo boost.

You have enough codes to get a new EGR valve I would think - that's the only 2 codes I had when they replaced mine.
Author:  greiswig [ Wed Jan 25, 2006 12:43 am ]
Post subject: 
Ranger1 wrote:
You have enough codes to get a new EGR valve I would think - that's the only 2 codes I had when they replaced mine.


That pretty much confirms my thinking, Ranger, although I'm still kicking myself for not looking for a code before I blocked off the pipe. Silly me...I thought if there wasn't a CEL, that there wasn't likely to be a code.

I'm going to run it blocked for another day or so, and see if anything else comes up. After that, I'll leave the p0401 code in place, remove the block, and see if the other codes appear. At that point I'll go to the dealer.

However...given my LOW confidence level that they have an EGR valve design that has better longevity, it's tempting just to leave it blocked off. Sheesh
Author:  Ranger1 [ Wed Jan 25, 2006 1:29 am ]
Post subject: 
I hear you... although, at this point, I still find it difficult to fault DCX entirely for the EGR issue, given the poor quality, high sulfur fuel we have to use, the ridiculous EPA requirements that indirectly make EGR feedback a necessity BEFORE ULSD diesel fuel is available and the fact that seemingly the EGR problem isn't an issue in Europe. But, if you have to wait for a new EGR valve, I would say that DCX would have no excuse for that after all of the failures they've experienced.

I'm at 7K miles on the replacement EGR, and my old one went at 8K so I'm watching this closely to see if they really have designed around our fuel...

It still doesn't make it a pleasant owner experience, but overall, I think I would rather have the opportunity to buy a diesel now and deal with the poor fuel/egr issue rather than have to wait until 2008.
Author:  greiswig [ Wed Jan 25, 2006 2:03 am ]
Post subject: 
I agree about the EPA problems, etc. However, I've run a minimum of B20 since new, and usually somewhere in the range of B70-B99 biodiesel. That should have pretty low sulpher content, even with the petrodiesel mixed in. To me, this implies that they should be seeing similar failure rates in Europe is sulpher content is the issue. So I can't help but wonder if it is something else.
Author:  Ranger1 [ Wed Jan 25, 2006 2:11 am ]
Post subject: 
I think our EPA NoX requirements are harsher than the European standards. Probably resulting in more active cycling of the EGR valve and more exhaust duty cycle I'm thinking. Who really knows. But I did read a blurb one time that the CRD emissions software had to be totally rewritten to meet US specs... lots of room for bugs there!
Author:  grywlfbg [ Wed Jan 25, 2006 1:02 pm ]
Post subject: 
So auto parts places will check for diag codes for free? Anyone know if Pep Boys will do this? I don't know of an Autozone near me. This worries me that you can have codes but not a CEL. I too have noticed a decrease in mileage but I'm not very dilligent in my computations so I've chalked it up to computer error or a mix of trailer, commuting, and highway duty giving me lower than usual readings. But I'd like to see if I have these codes.

Will the on-off-on-off thing display codes even if they're not causing a CEL?
Author:  valkraider [ Wed Jan 25, 2006 1:18 pm ]
Post subject: 
Ranger1 wrote:
II still find it difficult to fault DCX entirely for the EGR issue, given the poor quality, high sulfur fuel we have to use, the ridiculous EPA requirements that indirectly make EGR feedback a necessity


No. This is 100% a DC problem.

Volkswagen can make cars that meet the requirements, and have been doing so for years, and they have minimal problems.

The only real common problem that VW has with the EGR system is their tendacy to clog after tens of thousands (50 or 60 thousand) of miles on dirty fuel. Which is easy enough to prevent, either by adjusting your EGR parameters with a VAG-COM (still keeping them within spec and meeting EPA requirements, just adjusting different than stock) - AND/OR using cleaner fuel - like Biodiesel or high quality diesel - AND/OR using additives like PowerService to help keep your system clean.

But the VW problem is not a malfunction, so much as a maintenance issue. As if it clogs up you can clean it out reasonably easy (not SUPER easy, but not a major job either).

The DC CRD seems to have a faulty EGR that FAILS. It is not a "poor long term maintenance issue" - it is a "this thing freaking breaks after a few miles" issue.

That is a design or production issue. Maybe the design is OK and there was just a batch of bad EGR systems. Maybe the computer programming is off. Maybe it is just a bad design and needs to be improved.

I mean the things are failing at less than 10,000 miles. I personally think it was probably a bad batch... But maybe I am just hopeful, since I own a CRD. :)
Author:  Ranger1 [ Wed Jan 25, 2006 5:18 pm ]
Post subject: 
"No. This is 100% a DC problem."

I'm not yet convinced of that. For one, the CRD EGR valve is made by either Pierpont or Bosch( I don't remember which at the moment), not DCX. For another, the VW TDI is a much smaller engine, using a smaller quantity of recirculated exhaust gas than the larger CRD engine. Less gas flow through that valve, the longer time to clog it up. Also, some of the TDI owners who used the VAGCOM to reduce the EGR duty cycle, have reported that they still had clogging issues with their EGR valves. That fix works for some, but not all TDI owners. Well documented on Freds TDI site. Especially nasty looking is the picture a TDI owner posted of a completely blocked EGR valve - solid couple of inches of carbon. VW did the same thing Jeep/DCX did - they scrimped on the oil-air separator/ccv component and they get plenty of oil blowby right into their intercoolers, egr's and intakes. Now that's something that could be improved right from the factory. It's common enough that they (Freds TDI site) have HOWTO's on how to clean the intercooler, clogged EGRs and intakes...

Further, because DCX doesn't manufacter the EDC16 common rail system for the CRD, EGR valves, or glow plugs, but purchase it from a supplier, they are somewhat dependent on those suppliers to get it right. So there are issues, but not just with the CRD diesel - at the Jeep dealership where they replaced my EGR, they had plenty of Mercedes Sprinters with failed EGR's - the service techs told me of the extreme dissatisfaction of some Sprinter owners with high, out of warranty repair costs when their very expensive EGR valve failed, in the same manner our CRD's did. Some less than a year old. So there are differences in our fuel and emmissions maps that the European designers don't fully understand yet.

But, as to the delays many of us have run into with the Star network on getting replacement EGR valves and glow plugs parts, there isn't any excuse for that. That is just poor support logistics.
Author:  greiswig [ Wed Jan 25, 2006 6:55 pm ]
Post subject: 
Ranger1 wrote:
(SNIP)and glow plugs parts, there isn't any excuse for that. That is just poor support logistics.


Say, when the glow plugs are madly burning away trying to keep the cylinder temps high during an EGR failure, is there any indicator on the dash that this is happening? Does the glow plug indicator light up then, or only as a timer to tell the user when it's okay to crank?
Author:  Ranger1 [ Wed Jan 25, 2006 7:00 pm ]
Post subject: 
My glow plug indicator light never came on except for when first starting... according to the FSM, they will stay on after the light goes out, running for up several minutes if needed. Too bad there isn't a warning for excessive use... guess it doesn't happen often enought to warrant the extra code.
Author:  naturist [ Wed Jan 25, 2006 7:46 pm ]
Post subject:  I got news for y'all
My EGR failed at about 4500 miles, the replacement failed less than 100 miles later, and my third one appears to have failed another 300 miles after that.

Actually, all told I have 6500 miles on my Libby now, having driven many miles with the CEL alternately on and off. I ran the entire 4500 initial miles with B50, and have been running varying mixes since between B5 and B30. I have NOT seen any performance issues, however. But every time I take it to the dealer for the CEL, he sez "yup, EGR codes, got a bad one."

He also has expressed concern over the soot and oil in the intake and EGR.

Given the 100 and 300 mile failures, I disagree that it is related to soot buildup. There is something else going on here, but I don't know what it is.

I also have a VW TDI, and note that while they have their issues, failed EGR isn't one of them. My TDI showed a black oily film in the intake and EGR at 50,000 miles, but only a thin film, and with over 100,000 miles now there is no sign either of EGR problems or intake clogging.

I have to agree: DC has a problem all their own here with this issue.
Author:  greiswig [ Wed Jan 25, 2006 8:53 pm ]
Post subject:  Update of my own...
naturist wrote:
My EGR failed at about 4500 miles, the replacement failed less than 100 miles later, and my third one appears to have failed another 300 miles after that.(SNIP)


Interesting, indeed. One thing that's puzzled me about other people's posts is the descriptions of black exhaust from the tailpipe in otherwise good vehicles. I've yet to see any visible exhaust from this thing, something that I partly attribute to the biodiesel blends which tend to reduce carbon particulates substantially.

Update on my end: a couple of days now with the EGR blocked off, and the P0299 code is back, too. So apparently it *can* happen, Ranger1, even with the EGR pipe closed.

My mileage, OTOH, has gone up about 3-4 mpg, and I *think* turbo lag has reduced somewhat, but it's still there. Runs good this way. I'll have the dealer replace the EGR and see if I can get some pix of what it looked like.
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