Hey guys, So i have a 2007 6.0 f550 work truck. I am a mechanic but i am mostly a cummins guy but lately trying to learn the powerstrokes. First got the truck and it had been sitting for a while, had a misfire on 1 and 8. Put two new injectors in and misfire on 1 went away 8 was still there with some white smoke. Cylinder contribution test shows its missing and all the others are not. I put another new ford injector in and still missing. compression is about 370 when cold, valve train looked ok when valve cover was off. Pulled a FICM off another same truck we have here and same problem. So guys what else am i missing here? i would think if i had an oil leak it would effect more than one cylinder but idk. thanks for any help guys.
Also the only code is a p0284 cylinder 8 contribution fault. No check engine light on just that code keeps coming back. Only other thing i can think of would be the pigtail going to that injector? is that common on these? anybody have a pinout test diagram?
I have checked the connector and it looked clean and seated fully also i have checked the connectors on FICM and all were completely clicked on and look clean too. Misfire is only at an idle i believe because cylinder contribution numbers come up from -60 to -80 to 0 when I accelerate. maybe thats normal though?
you will see some negative numbers usually acrossed all 8 when you go off idle from what i have noticed. What doesnt make sense to me is that its a new injector so stiction shouldnt be an issue. when you had the stand pipes out did you notice what color the o rings were?
Yes i understand that but i am saying number eight is clearly negative when all others are between -10 and 10. I am guessing the stand pipes are the pipes that go down through the head right off the oil supply rail? If that is what you mean i can tell you the driver side o rings were black, but i didnt do the passenger side a guy in the shop did then it came to me when number eight was still misfiring.
Yes the stand pipes are the long pipe you have to unthread out of the oil rail to access the injectors.
The dummy plugs are also in the oil rail and just block the hole in the oil rail because the oil rails can be used on either driver side or passenger side heads.
The latest revision of these stand pipes can be identified by a while ring under the orings, also the dummy plugs are similar and slightly longer than the outdated version.
Also have you checked your FICM output it should be around ~47v and not drop below that.
I have not checked FICM output voltage. How do i do that? I figured i had ruled that out because our other truck had a brand new FICM and was running great so i stole that one and swapped it into this truck but still same issue.
Not 100% sure this could be the problem but i would consider replacing both dummy plugs and stand pipes, especially seeing how you have had the driver side removed it is more like to now fail. If they were black then they are the older version
I just worked on an 06 with similar problems to you except i only had #4 sticking. he had a hot no start condition but i knew he had the old dummy and stand pipes i replaced all of the above and now it runs great.
I would inspect the harness, pins and anything electrical to that injector, something sounds funky, maybe a chaffed wire, pushed pin or something of that nature.
If it is related to failing seals on standpipes or dummy plugs, you should already be seeing increased cranking time when starting hot. My *guess* is that they are not the issue because I've had then fail bad enough to barely start cold, but not affect injector function or throw codes of any kind.
How many miles on it? Possibly the ball cup/nipple that sticks down in the injector is scored, or the o-ring seal for it in the rail.
If it is related to failing seals on standpipes or dummy plugs, you should already be seeing increased cranking time when starting hot. My *guess* is that they are not the issue because I've had then fail bad enough to barely start cold, but not affect injector function or throw codes of any kind.
How many miles on it? Possibly the ball cup/nipple that sticks down in the injector is scored, or the o-ring seal for it in the rail.
To answer some of the questions. I pulled glow plug out and it looked ok i didnt test it though. Cranks and runs fine but has a misfire at idle. I looked at the pipe that goes into the injector and it looked fine no scoring or marks. Also it does run fine above an idle or so it seems.
Misfire even after warmup?
Is the misfire at all noticeable, or detected only with contribution test?
I've read somewhere on this site that #8 is always a little off due to getting less HP oil (I think). I don't know if that is true only for 04 and earlier or all, or...? Anyone have reliable facts on that?
Ok i am gonna take your advice and replace stand pipes and dummy plugs tomorrow. I have a snap on solus ultra scanner and I think i looked at FICM voltage but i will check tomorrow. My question is if i was losing oil pressure anywhere by number eight injector wouldnt it affect the other injectors in some sort of way or no? I dead headed all the other injectors with my scan tool and every single one besides number eight made a big difference in idle. Also does anybody have a pinout diagram so i can check resistance between number eight pigtail and FICM. It would make sense if it was an oil leak as higher rpms would boost oil pressure and make the injector run better. but i would think it would effect total oil rail pressure maybe i am thinking wrong? possibly a small enough leak by that injector to only effect that injector? just thinking out loud. how much would it be to replace the whole oil rail and stand pipes?
Just to be clear im quite sure the dummys and stand pipes are not related directly to this problem but more than likely will become a problem down the road. If you have a snap on solus scanner you can perform functional tests on your truck as long as its updated through your model year. An injector buzz test, glow plug KOER test will help you pinpoint your problem with #8 Under data display > engine data you can view your FICM voltage, ICP psi. IPR% etc. Typically an oil leak will affect all injectors on that bank. I highly doubt an issue with the oil rail its self but i would inspect where it connects to #8 for damage. Hope this helps
When you replaced #8 it was the closest to the firewall on the driver side correct?
yes misfire even after warm up at idle. smokes when cold. Noticeable most the time but intermittent for sure. The time that i spent looking at cylinder contribution while misfiring was always about the same -60 to -80 whether i could feel the misfire or not.
I would never try to talk someone out of installing updated dummy plugs (old ones will all fail, most way too early) and standpipes (seem to far outlast dummy plugs but most rubber seals will fail eventually). But I seriously doubt they will fix your misfire problem.
Seems to me rails are >$500 each.
If you find yourself pulling the rail again, swap #8 injector with one of the others to see if the misfire moves with it. It is not impossible to have gotten a bad one.
Yes sorry i thought i covered that before it was smoking, white smoke when cold. Also this is the second new injector from ford. How much for standpipe and dummy plugs?
Like i said all injectors on that bank are running great. maybe i have such a small leak that its only effecting number 8 when hpop pressure is lowest at idle.
If you have the original EGR cooler, do that and maybe the oil cooler while you have it apart for the STC. (Do an upgraded aftermarket EGR cooler and ELC coolant, or the EGR delete if you are OK with that approach) Read up on why these are inevitable and worth doing all at once.
Update, this morning I thought i had it fixed there was a ground on the exhaust shield that had broken but that didnt fix it! I have got the valve cover off and i am running it now and its still missing. where should i be looking for oil leaks guys? also my IPR is at 28-30% while idling cold. ICP is 830-840 and thats what desired is so i think thats good. Compared to a 7.3 that IPR percent seems very high. I am gonna go check my other 6.0 i have here.
Those numbers seem reasonable but probably mean very little. At OT of 200f I've seen 585 @ 242.8% yet the leaks are bad enough it won't make 200 psi hot crank.
And really, if your prime focus at the moment is the misfire, HP oil leak is low on the list unless the leak is at that injector. Seal in the top, the nipple that goes into the top, the seal in the rail at the base of the nipple, or maybe the seals in the body of the injector. The air tests may not be definitive, they certainly are not for me, but it is worth doing.
I forget, did you check the injector harness? FICM voltage OK when running? Run a buzz test?
How bad is this misfire?
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