Alex Bruene Posted November 6, 2017 Share Posted November 6, 2017 Here goes... I have an ongoing P207F (I think the F stands for "fuck me")... This is my second go at this one. To skip to my issue, this truck always fails the DEF injector cleaning. It has a known good injector, the dosing measurement and spray patterns are fine, and the pressure remains above 72 psi during the test. When following PPT RK, step 7 says to run the injector cleaner, and if it fails, replace the injector and rerun the test. What it doesn't tell you is where to go if he injector cleaner fails with a good injector. When I remove the injector, install it on another vehicle and run the cleaner, it passes with no issues. The last time this truck was in, hotline told me to disregard the failed injector cleaner and continue on with PPT RD. That eventually lead me to replace NOx12. So I replaced both NOx sensors. Now, the truck is back with the same issues. Still fails the injector cleaning. When I skip past the failed test, it eventually leads me to replace the DPF, which is fine, as I've replaced DPFs for P207F issues before. Now, what I don't know is how the IDS determines the state of the DEF injector, and could an issue with the SCR catalyst give me an erroneous fail on the injector cleaning? This is a retail job, so I don't want to call a DPF until I'm more certain about the diagnosis. Thoughts? Quote Link to comment Share on other sites More sharing options...
mchan68 Posted November 6, 2017 Share Posted November 6, 2017 I've had one such truck with an engine hour count, equivalent to double the actual driven mileage needing two DPF/SCRs to repair P207F if that helps much. The first go around under warranty, and the second one was good willed because his FMPP is still a long way from expiring. Not that it helps much, but I really don't understand why the exhaust after treatment system doesn't have the same coverage as the diesel engine system components. Oh, and on that particular truck my manager actually asked me if there was way to delete that system. You can imagine how that conversation went. Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted November 6, 2017 Author Share Posted November 6, 2017 I got a pretty good answer from hotline on my issue. Alex, During the Injector Cleaner routine, the PCM is looking for an appropriate response between NOx11 and NOx12 sensors. It is looking to see that the NOx gasses are being reduced by a calculated amount. If it does not see this reduction, it fails the cleaner routine thinking that the reductant injector is not dosing the correct amount of DEF. However, since the Dosing Test, Leak Test, Concentration Test, and Contamination Tests all prove that the reductant system is operating correctly; it is likely that the SCR is not reducing the amount of NOx gasses properly. Thus tricking the PCM into failing the Reductant Injector Cleaner routine. 1 Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted November 6, 2017 Share Posted November 6, 2017 Or - confirming that the SCR is bad. Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted November 6, 2017 Author Share Posted November 6, 2017 1 hour ago, Keith Browning said: Or - confirming that the SCR is bad. Or that... 1 Quote Link to comment Share on other sites More sharing options...
Alex Bruene Posted November 8, 2017 Author Share Posted November 8, 2017 After what I thought was a good answer from hotline, I received an update to my report that Ford had escalated the concern (without my requesting escalation). They told me to hold off on replacement of the DPF until they can do some over the phone diagnosis with me. Quote Link to comment Share on other sites More sharing options...
mchan68 Posted November 8, 2017 Share Posted November 8, 2017 Threads like this make me wonder why Ford can't make the DOC, SCR and DPF as separately serviceable components like they are on the 2016 and up F-650/F-750 models. Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted November 8, 2017 Share Posted November 8, 2017 I think you know the answer to that Mike. $$$ as it is most likely most cost effective to mass produce these systems as an assembly than separate parts that require additional machining, attaching hardware and labor/time to assemble. And I am sure the cost savings far outweighs the projected warranty cost for replacing them when you plug in all of the numbers. But I agree that if they were separate life might be easier for us in the service bays. Quote Link to comment Share on other sites More sharing options...
JoeR Posted November 8, 2017 Share Posted November 8, 2017 Separating the components would also allow cleaning DEF deposits near the Injector. That'd be my next move if i was working on a big truck. It's not possible on a 6.7 ford though. You might be interested to know I have a friend that puts these exhaust systems in a band saw to separate the parts, cleans them, and TIGs them back together. Joe Quote Link to comment Share on other sites More sharing options...
mchan68 Posted November 9, 2017 Share Posted November 9, 2017 9 hours ago, Keith Browning said: I think you know the answer to that Mike. $$$ as it is most likely most cost effective to mass produce these systems as an assembly than separate parts that require additional machining, attaching hardware and labor/time to assemble. And I am sure the cost savings far outweighs the projected warranty cost for replacing them when you plug in all of the numbers. But I agree that if they were separate life might be easier for us in the service bays. Not just easier for us in the service bays, but more or less keeping the out-of-warranty repair costs reasonable for the consumer. Let's face it, most of these trucks are workhorses for their owners, who for the most part are willing to pay the price of repair to keep them roadworthy for many years. But c'mon, having to pay the outrageous price to replace the exhaust torpedo because the DPF can no longer complete regens to clean it, or as in this thread's topic to complete repair to P207F setting, is a bit much don't you think? Yeah, I agree with it being cost effective to the manufacturer, but at the expense of being cost prohibitive to the end consumer when out-of-warranty replacement is required. No wonder there are so many guys out there doing deletes. Quote Link to comment Share on other sites More sharing options...
Keith Browning Posted November 9, 2017 Share Posted November 9, 2017 Here is another argument for replacing the assembly that I just realized. Which catalyst are you going to replace in this situation and why? Is the DPF not capable of properly lighting off preventing proper SCR function? Is either catalyst broken or poisoned? Is the SCR plugged to the point where is cannot be cleaned with heat? (i had one SCR that was nearly totally face plugged with crystallized DEF that would not clean after a couple of manual regeneration attempts) Replacing them both removes the possibility of not replacing the part that is really at fault and it likely could be both, the "cause and effect" scenario. I guess I am saying that it would cause more confusion if the fault/code returns and the customer would likely be more pissed not to forget that you still need to determine what caused the aftertreatment system to become damaged or ineffective in the first place. Oil or coolant contamination? Something in the fuel? Something in the DEF? A bad sensor or NOx module? I wish Ford would develop an IDS function that performs a cleaning of the catalysts and test their function automatically. It would save a lot of time and confusion. Cummins has it. I have used it and it is one of the few joys of using the Cummins INSITE software. Isn't our job fun? Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted November 9, 2017 Share Posted November 9, 2017 12 hours ago, JoeR said: I have a friend that puts these exhaust systems in a band saw to separate the parts, cleans them, and TIGs them back together. Joe Yes, that's not uncommon now. I recently saw a jig that D&W Diesel has for welding them back together after cutting, cleaning, etc. Quote Link to comment Share on other sites More sharing options...
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