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I highly suggest asking this in the powerstroke.org forum. There are many knowledgeable 6.7 minds in there.
6.7 Powerstroke Diesel Injectors failing at low mileage?
- Thread starter mbacfp
- Start date
Is the tech a trained diesel expert? There are some around but not every mechanic is. diesel expert.
Have they load tested all the injector wiring for that cylinder injector? They need to make sure pin drag is good on the pcm connector. Unlikely pcm is the issue.
There is most likely a wiring issue, a pin fitament issue or a ground problem.
first thing I would do is clean all pcm/chassis to battery grounds.
I would also ohm out that entire injector circuit from the pcm connector. Depending on what I find I’d do a temporary overlay of the wiring right to that injector and de-pin those 2 pins at the pcm connector and drag them across the terminals at the pcm to make sure they are making good contact. The tech should be able to find the problem doing these steps pretty easily.
There is most likely a wiring issue, a pin fitament issue or a ground problem.
first thing I would do is clean all pcm/chassis to battery grounds.
I would also ohm out that entire injector circuit from the pcm connector. Depending on what I find I’d do a temporary overlay of the wiring right to that injector and de-pin those 2 pins at the pcm connector and drag them across the terminals at the pcm to make sure they are making good contact. The tech should be able to find the problem doing these steps pretty easily.
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Yes, an independent diesel shop.
Appreciate it. Will reclean battery connections to rule that out. I am hoping all that was done. I'll have to look into that to verify if cleaning batteries doesn't help. Will keep thread updated on this. Very much appreciated all.
Update...looks like new injector for P1557 is now showing code at every start up. So, P1555 and P1557 now show. I clear and drive. Engine runs smoothly, MPG is good and no smoke. Ford dealer told me bad and replaces (P1557) and they did a PCM refresh which I wonder if it causes the codes to stop for a bit? Thinking PCM needs replacement?
Thinking about getting programed PCM to see if that fixes it. Are they hard to replace on a 6.7 powerstroke? Other diesel forum has no answers on things so far.
Have a great week all.
Thinking about getting programed PCM to see if that fixes it. Are they hard to replace on a 6.7 powerstroke? Other diesel forum has no answers on things so far.
Have a great week all.
Between the two places...I assumed they did. Planet Ford in Spring, TX (P1557 code) has a dedicated truck center...but I don't know. Shop tech said (non dealer - P1555) said he ran a bunch of tests and couldn't do one due to it being a Cab & Chassis. All was functioning good. When I get back home I need to call shop and see if I can get confirmation on all that was done. Will keep thread updated. Appreciate all the help and advice.
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emissions. ULSD was the start of lubricity failures in every aspect of the diesel world.
i ripped out my garbage 6.7 and stuffed in an old school used 5.9 cummins with 700k on it before the swap, even comes with auto-drip rust guard for the truck frame. Half it's diet isn't even diesel fuel. I won't post exactly what so the tree huggers won't flip out. And no, not biodiesel.
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I like the 8.3 swaps they do with the f-450s
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I may need to research and make sure they still use bio diesel. I asked the tanker driver at buccees, and he said it's in there a while back. Uses to use standalone lubricity formula and nothing made the truck run as smooth as that stuff. I quit using it because the bio diesel is supposed to be better
Yep.
I'm keeping all of my old school 1 wire fire diesels. Built a small building to house them all. Same with all the manual gearboxes, xfer cases, and PTOs.
Blue tip wrench ajd some 240v hot glue sticks is all I need to do a swap.
Currently stuffing in an old 6.9 IDI into a nice southern 2018 f350 long frame.
She's gonnna have a regular cab, with a 12ft box, 8ft wide, and 4ft tall, and hydraulic dump from the PTO hanging on the side of the BW. None of that electric/battery bull sheet.
Something useful that lasts that isn't available. Quite the combination.
Disgusting spending $100k+ on a diesel that doesn't last, choked to the point it destroys itself, then an electric dump hoist??? Turn that pump off the crankshaft like a real man.
Good god. What's the manufacturing world coming to??? "Real" trucks have at least 3 sticks poking out the floor. Gearbox, xfer case and PTO.
I'm keeping all of my old school 1 wire fire diesels. Built a small building to house them all. Same with all the manual gearboxes, xfer cases, and PTOs.
Blue tip wrench ajd some 240v hot glue sticks is all I need to do a swap.
Currently stuffing in an old 6.9 IDI into a nice southern 2018 f350 long frame.
She's gonnna have a regular cab, with a 12ft box, 8ft wide, and 4ft tall, and hydraulic dump from the PTO hanging on the side of the BW. None of that electric/battery bull sheet.
Something useful that lasts that isn't available. Quite the combination.
Disgusting spending $100k+ on a diesel that doesn't last, choked to the point it destroys itself, then an electric dump hoist??? Turn that pump off the crankshaft like a real man.
Good god. What's the manufacturing world coming to??? "Real" trucks have at least 3 sticks poking out the floor. Gearbox, xfer case and PTO.
That 6.9 will do what you need and get you where you are going but you will always be late.
Only people I've noticed in life who are in a hurry are the race boys and SEMA weiners.
Just completed a 1,700 mile round trip (camping). Ford paperwork on the P1557 injector doesn't go over any tests, but says changed injector (not pigtail). New injector for P1557 and new injector and pigtail for P1555.
After every start I either get P1555, or get both P1557 & P1555. Truck has no performance or MPG issues. Delete and go...only comes back on after restarting...never after Delete while on.
Other tech said PCM...Ford replaced and reflashed PCM for P1557 and bought be 2,000+ miles before coming back up. Unfortunately, I'm past 1 year for warranty repair.
Maybe find another shop to diagnose or throw a new programmed PCM at it?
Would like to fix and not keep deleting...but kinda of stumped.
Throughout the life of the truck I've had a couple of instances when the truck started and dash went completely dark and had to turn off and restart and came back on.
Appreciate it. Thanks for listening...hopefully this journey will help someone else?
Happy 4th all.
After every start I either get P1555, or get both P1557 & P1555. Truck has no performance or MPG issues. Delete and go...only comes back on after restarting...never after Delete while on.
Other tech said PCM...Ford replaced and reflashed PCM for P1557 and bought be 2,000+ miles before coming back up. Unfortunately, I'm past 1 year for warranty repair.
Maybe find another shop to diagnose or throw a new programmed PCM at it?
Would like to fix and not keep deleting...but kinda of stumped.
Throughout the life of the truck I've had a couple of instances when the truck started and dash went completely dark and had to turn off and restart and came back on.
Appreciate it. Thanks for listening...hopefully this journey will help someone else?
Happy 4th all.
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Appreciate it. Let me find another shop and arm them with this situation...maybe they can take a more targeted approach based on what is happening. The last tech said he checked all grounds and wires, etc. Don't know about exact diagnostics though. Either way, will keep everyone updated. No trips planned for a while so need to get this figured out. Thanks again Mattd...you have helped me in the past with your knowledge. Thanks for your time and knowledge. Happy 4th all.
Many times in situations like this, resistance checks are not enough. The wiring must be load tested, and the pins on the connectors must be drag tested outside of the connector
Whoever writes diagnostic flow charts need to spend some time in the trenches...I roll my eyes every time I read checking resistance when it comes to wiring & connections.
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