Aaron Posted July 14, 2008 Share Posted July 14, 2008 So I'm at the roach coach this morning, getting my coffee, and Shlep comes up to me and says "You're a see-lebrity!" - he hands me a copy of June's Diesel Power magazine, where I spouted in a letter about their EGR cooler delete bit. They published my letter, in which I stated the EGR valve is an integral part of the fail-safe system in the air intake to help bleed boost if necessary. Editor of the magazine says "No way" and says that's the VGT's job. I am unable to find documented anywhere the co-relation of the EGR and VGT systems. I would like to offer a rebuttal, but I'm having a hard time explaining how they are tied together. I know how it works in my head, and I know how to diagnose it on a car, but I'm having a hard time explaining how they are tied together - and I don't like being told I'm wrong in front of millions of readers. Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted July 14, 2008 Share Posted July 14, 2008 This is a PCM strategy that I have seen in action and have recordings of... I think. Around 26 PSI of sustained boost or higher, if the PCM cannot reduce boost with the VGT actuator the EGR will be opened to bleed off some of the exhaust and slow down the turbo. I don't think I have seen this documented either but I recall a conversation with the hot-line where this was confirmed but there may also be other things happening as well. Whether this is a part of the PCM strategy or not, it does work. With the problems we have with sticking turbochargers I am surprised this is not better known and documented. ... that is, unless I am totally wrong. Quote Link to comment Share on other sites More sharing options...
DwayneGorniak Posted July 14, 2008 Share Posted July 14, 2008 You may have to do some recordings Aaron and send them to the editor to help explain the relation. Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted July 14, 2008 Share Posted July 14, 2008 You know what, Aaron... I've been stuck in the same arguement on a public forum about the exact same thing. Unfortunately, it was put on me to prove that the EGR system DOES just that, not on my opponent to prove that it DOESN'T do it. I was told this is a strategy by our service school diesel guru, and have no reason to not believe him. Remember, we are fighting a losing battle against those who don't know chit, but still, are always right... as far as they are concerned. Quote Link to comment Share on other sites More sharing options...
Aaron Posted July 15, 2008 Author Share Posted July 15, 2008 I was told this is a strategy by our service school diesel guru, and have no reason to not believe him. This is where I was basing my statement, the teacher I had (We likely had the same one, as I see you're from Toronto) told us exactly the same thing, and it was one of the class scenarios, if I recall rightly. Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted July 15, 2008 Share Posted July 15, 2008 I know I have a screen shot or recording showing this in action but if you need to see this for yourself, bring in a 6.0L equipped truck and get it to operating temperature. Hook up IDS and start your session, open data logger. It's time to play. 1- Select these PIDS; EP, EGRDC, EGRVP, MGP, RPM & VGTDC 2- Select the following PIDS and command each as listed: Raise RPM to 1200 Command VGTDC to 85% (You should hear it spool up) Command EGRDC to 0% Note and record EP, MGP and EGRVP. Open the EGR valve by commanding it open to 45% Note and record EP, MGP and EGRVP. What did the data show? How did the turbo sound when the EGR valve opened? You should have heard the turbo and the engine "go quiet." Notice that with RPM and VGTDC at steady state, when the EGR valve opens, EP will drop causing the turbo to slow down resulting in a decrease in MGP. If you could demonstrate this to someone who disputes this... Quote Link to comment Share on other sites More sharing options...
Aaron Posted July 15, 2008 Author Share Posted July 15, 2008 Keith that was the first thing that popped into my mind when I was looking through my 6.0 notes. I was hoping there was a piece of PC/ED manual I could quote or something, because I have a feeling that if I send that to these guys they will just look at it like "Whaaaaaa?" Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted July 15, 2008 Share Posted July 15, 2008 The other thing is, if every single operating strategy of this engine were to be published, I'd hate to see the size of the book! Quote Link to comment Share on other sites More sharing options...
LARRY BRUDZYNSKI Posted July 15, 2008 Share Posted July 15, 2008 Aaron I think this may help out a little bit.... http://www.grufmanbil.se/mektips/6.0l_2003.25_turbocharger_guide.pdf Quote Link to comment Share on other sites More sharing options...
Aaron Posted July 16, 2008 Author Share Posted July 16, 2008 That's a REALLY good read Larry, but I think that it'd confuse them even more. You know what might work out guys? Everyone go here http://www.dieselpowermag.com/contactus/index.html and drop them a quick note how you read the letter by Aaron Robertson from Windsor Ontario with great interest, and thought they should be corrected on their EGR/VGT strategy. Letter: I read your article regarding the 6.0 pow4r stroke EGR cooler delete. You do realze the EGR is a failsafe for too much boose, which is one of the main causes of head gasket failure on the 6.0 So, an aftermarket turbo or wastegate would also be a reccomended upgrade. The other point i'd like to comment on is your statement that the EGR cooler causes the coolant to boil. Generally this is not the case. loss of cooling system pressure or introduction of air into the cooling system (generally once it passes the capacity of the pressure cap on the degas bottle) due to excessive cooling pressure because of too much boost, is what causes the egr cooler to fail. Readers that would like to increase their 6.0's reliability while keeping their truk emissions leaga should consider using an early build 03 to 04-1/4 egr cooler that uses a tube style element. editor's response: We disagree with your assessment of the EGR system accting as an over-boost fail safe (That's the job of the VGT), we do like your suggestion of using the early model 6.0 EGR cooler. My thoughts: A number of things bother me about this letter, mainly the fact that it's been heavily edited, including my self-identificaiton as a powerstroke tech., as well as some other information that I included to make myself not look as stupid as the above letter does. Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted July 16, 2008 Share Posted July 16, 2008 Aaron, before confirming this with a Navistar Field Service Manager today I was confident that the 6.0L PSD does in fact have a strategy that attempts to reduce Turbocharger speed by opening the EGR valve. I am now certain. I would be willing to send them my thoughts but I would first like to read the article or column that was written containing your letter. Was this in print or on-line as well? I cannot find it on-line. Quote Link to comment Share on other sites More sharing options...
Jeff_E Posted July 16, 2008 Share Posted July 16, 2008 Check out Web course 51G07W0 (FIRTFT 6.0 Turbocharger Diag and service) Look under the 6.0 Turbocharger operation tab / Turbo, EGR, and Exhaust interaction sub tab. It didn't mention this specific protection strategy, but it did emphasize the relationship between the two components and how a fault in one would effect the other. I too could have sworn that they went over this protection strategy in the 6.0 drivability class. I went on Stars to see if I could download the course material, but for some reason it isn't available online anymore. If I remember right, our instructor even bugged a truck to do exactly this and made us figure out why. I know the bug he performed was to disconnect the EP sensor, and plug the connector into an extra EP sensor he had, which wasn't plumbed to the exhaust manifold thus fooling the pcm into thinking EP was much lower than it actually was. This caused the truck to overboost for a short while before the MAP reading concerned the PCM enough to restrict boost to 11psi - or something like that... I was under the impression the PCM accomplished this by opening the EGR partially to bleed off boost - but It's been years so who knows. I suppose one could make a recording of such a bugged vehicle and see how the EGR pid changes to know for sure. /forums/images/%%GRAEMLIN_URL%%/scratchhead.gif Quote Link to comment Share on other sites More sharing options...
jared_bortel Posted July 16, 2008 Share Posted July 16, 2008 Althought I do read diesel power I have greatly lost faith in their technical knowledge. They published an article a couple months ago about putting head studs in your 6.0l. It stated how you need to be careful when removing the head gasket not to seperate or damage it, SO IT COULD BE CLEANED AND REUSED. Seriously? Quote Link to comment Share on other sites More sharing options...
Shlep Posted July 16, 2008 Share Posted July 16, 2008 Althought I do read diesel power I have greatly lost faith in their technical knowledge. They published an article a couple months ago about putting head studs in your 6.0l. It stated how you need to be careful when removing the head gasket not to seperate or damage it, SO IT COULD BE CLEANED AND REUSED. Seriously? I'm glad you brought that up because I read that as well, from that moment on I stopped buying that magazine. Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted July 16, 2008 Share Posted July 16, 2008 And we're the ones that don't know what we're talking about... /forums/images/%%GRAEMLIN_URL%%/banghead.gif Quote Link to comment Share on other sites More sharing options...
Aaron Posted July 16, 2008 Author Share Posted July 16, 2008 Keith, it was a magazine article regarding the deletion of the 6.0 EGR cooler. PM me your mailing address, I'll mail you the pages of the magazine, as I don't have a scanner. Don't let me get too far ahead of myself here, I'll have to find the magazine first. Quote Link to comment Share on other sites More sharing options...
dieseldoc Posted July 19, 2008 Share Posted July 19, 2008 I have really lost interest in the diesel power magazine. They must have changed editors or something. It is not as good as it used to be. There technical knowledge is really lacking and there article choices of late have not been that great. I know when my subscription is up i wont be renewing it. Quote Link to comment Share on other sites More sharing options...
HeuiTim Posted July 20, 2008 Share Posted July 20, 2008 Aaron, Congrats on being published, that was your first mistake. Your second mistake is correcting an editor. Man-eye-ical nazi's are not interested in your knowledge. They write to hear themselves talk(huh)kind of like me. Let them be mis-informed and wrong, the only people who you need to worry about are the ones who know you are right. Let the 'tards blow up their stuff, more work for us. Remeber you can't help stupid. A Cat example (because thats all I know-and thats up for debate) was the C7/C9 Smart Wastegate. Dummies were tring to defeat it thinking it limited boost. The system would actually allow more boost during high demand periods, it improved performance but the 'experts' were trying to defeat it. Tim Quote Link to comment Share on other sites More sharing options...
Aaron Posted July 22, 2008 Author Share Posted July 22, 2008 Example: 6.0L head gaskets - Wash and Re-use! /forums/images/%%GRAEMLIN_URL%%/rolleyes.gif Quote Link to comment Share on other sites More sharing options...
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