Brad Clayton Posted August 26, 2011 Share Posted August 26, 2011 2011 6.7L don't run so good with only code in system P0087. Now I read the pinpoint test for this code more than once and it's about as wild a goose chase as the nox codes. I think the guys that wrote this PCED could have paid a little more attention to the 6.4l diagnosis. Every P0087 code I have run up on ended up being fuel filters or low pump. I'm not saying that other stuff doesn't break. I am also not saying that everyone should disregard the shop manuals. But common sense has to take over at some point. I did not follow the PCED in this case, although if the truck would not have run at all, the no start symptom chart would have ended up with the same result in a painfully agonizing drawn out way. So my truck actually runs, with low fuel code. I decided to see what the actual fuel pressure is using the 5 gauge set and adapter at the secondary fuel filter. KOEO and this is all I could get: This is way under the 55 psi spec. and the pump can put out at least 120 psi. So a new set of overdue filters were put in with the same result and a noisy pump followed. The low pressure pump was replaced and the fuel system was bled by removing the return line at the fuel cooler and the pressure was: So this truck ran like a dream when done. Just a suggestion if you encounter this code, check the low fuel pressure with a gauge. If it's ok, great move on with the pinpoint test. If it's low I wouldn't go any further until the mechanical is squared away. Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted August 26, 2011 Share Posted August 26, 2011 I am going to be an absolute dick... right now and right here. Reading carefully is something that every last one of us has trouble with... major trouble with. At the same time, it is of the utmost importance that we read and understand everything that is handed to us. If we go to the diagnostic trouble code charts, we see that the code defines as "fuel rail/system pressure too low". OK... we are looking at a cause for low fuel pressure as measured by the fuel rail pressure sensor. Scrolling down a tad, we see what is "going through the PCMs brain". Scrolling down a bit more we see "possible causes" - and the number one possible cause is "low pressure fuel system". "Yeah,yeah,yeah... what the fuck is all this shit... what PPT do I need?". One of the biggest mistakes we can make is to expect the manual to grab our hand, and lead us to the miracle cure. Because the manual is busy assuming that we are trained techs and can make informed judgement decisions on our own. Getting back to basics. This is about the most important consideration we can have. We allow ourselves to be seduced by the scan tool and the PC/ED. The promise of keeping our mittens away from dirt and hot engine components overwhelms us. Looking professorial as we wrinkle our brow at an IDS screen becomes an image we want to foster. The scan tool allows us to do things we could never imagine 10 or 15 years ago... but there are still many things it wont allow us to do... Basics.... I can't say it often enough... basics. If you are still with me, let us pretend that you are working on a 2008 SooperDoodie gas..... It has a P2112 in memory (of course it will also have a P2104). This code will take you to PPT DV3. The first questio9n we ask ourselves at this point is "what does the test try to determine?". It wants to check the open volts and closed volts reading of the TPS... basically... it is asking (when we stroke the foot feed) if the throttle plate is moving and, if it is, does our high reading fall within expected values and does our low reading fall within expected values. If we watch closely and stroke the pedal at different speeds, we can determine if we have other concerns (like a "tight spot" or sensor dropout). Here lies a cause for concern... if the answer is yes, the readings are within the guidelines... go to DV4. If the answer is no, one or more of the readings is outside the guidelines.... go to .... ermmmmm go to DV4. Wow... I'm glad I did that test. Without a doubt, there are times to be pissed at the manuals... Like when creating a condition that should set a P0232 and having it set a P0231... or having a "pass" send you to the same PPT as having a "fail". When we deal with body control type modules (HVAC, GEM, DSM ACM and Gawd knows what all else any more) there is usually a list of fuses to check in the introduction.... but few techs ever read the introduction and cut straight to step one of the PPT. Spending an inordinate amount of time learning that they didn't need to spend all that time... and possibly "cooking" a cover story. Brad... you have a golden learning experience on your hands. Don't worry, I made this exact same type error in judgement myself - many years ago.... When push comes to shove, it boils down to the fact that I get paid to read... Everyone else has been "flat rate reading" (something I still do far too often) and now it is my turn. When "Tech A" has 20 hours into a diag and replaced hundreds or thousands of dollars in parts out of frustration. We can be sure that he has overlooked something basic - something overwhelmingly simply. I am told that, as of Sept 01, I am no longer shop foreman. (I may divulge that soap opera later). Quote Link to comment Share on other sites More sharing options...
Brad Clayton Posted August 26, 2011 Author Share Posted August 26, 2011 I have been wound up tight lately and I really should have looked in the mirror when trying to find a fault. Quote Link to comment Share on other sites More sharing options...
Bruce Amacker Posted August 27, 2011 Share Posted August 27, 2011 Those pumps look really cheesy to me and I wouldn't be surprised if we end up changing them regularly. Quote Link to comment Share on other sites More sharing options...
Jim Warman Posted August 27, 2011 Share Posted August 27, 2011 When travelling at a high rate of speed - i.e., something that may generate a P0297 on a paved road, current experience shows that most any loose object the left front tire encounters will plot a trajectory that will intersect the bottom of the fuel conditioning module. Other than that, we haven't seen many concerns with these devices. Still, Brads call to the low pressure fuel system is a valuable reminder to all of us that we desparately need to examine the basement before we get concerned about the shingles. These forums are a valuable resource in recognizing emerging pattern failures. Quote Link to comment Share on other sites More sharing options...
cheezit Posted August 29, 2011 Share Posted August 29, 2011 so fare have seen 3 of the exact same thing. replaced 3 pumps so far and 3 fixed trucks. now the issue is this ford says we have to follow the ppt test if we expect to get paid. My boss refuses to sign off on the pcms... and yet the back flags come from either not folloing the pc/ed or ineffective repairs when ya do Quote Link to comment Share on other sites More sharing options...
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