I have searched the web and here and cannot find a similar issue. My wifes Expedition has been running fine. The cam phasers chatter of course when its hot. With 170k on the odo thats to be expected though. A few days ago she drove to work .5 miles. shut the truck off for about a minute, and had to run back home. Upon startup, the truck runs horrible. It reeks of eggs out the exhaust and the CEL was flashing. I put my pocket scanner on it and got P0308 (#8 misfire detected). I limped it home since it was so close.

I figured typical COP probably bad since I put the updated hotter motorcraft 1 piece plugs in it 8 months ago (NONE BROKE!). After searching the web and locating the test procedures for the COP (original ford cop's), they all test out 1.3 ohms on primary side and 6k to secondary. Ive read about injectors on the 05 sticking, and also an issue with the plating flaking off inside the injector rails on the Expedition. However here is what I did. Please shoot holes in it or possibly get me pointed in the right direction...as long as its not the stealership.

1. Removed #8 coil pack tested good.
2. Removed spark plug, looked fine, typical small tan portion on the electrode insulator
3. Removed #5 coil pack and swapped it for #8, installed #5 COP on #8
4. Cleared codes.
5. Started engine, still super rough idle, shakes like crazy.
6. Scanned it and now have 3 codes P0300, P0307, P0308
7. Checked all of the connectors on injectors to make sure they were tight.
8. While running, unplugged the cop's 1 at a time and then plugged back in, #8 no difference. Unplugged #7 no difference. Unplugged #6 got worse. Unplugged #5 got worse. Unplugged #1 got worse, Unplugged #2 got worse. Unplugged #3 no change, #4 no change as well.
9. Did same procedure as 8 above but with injectors instead, no change on 3/4/7/8
10. Checked all fuses, none blown
11. Checked PCM ground, good.
12, Checked PCM connectors, clean and tight.
13. Wiggled/tugged on the harness from pcm all the way to the drivers side of the motor where the injector pigtails go on.
14. Checked fuel pressure. 45 when key cycled. 58 running in Park. Pressure holds at 40-43psi when key turned off, so assume no leaky injectors.
15. checked for voltage on the injectors, 12v on one leg with key on, 4.2v on other leg with key on engine running? Odd?
16. Checked for voltage on COP pigtails, 12v on one leg. Cant check pulse ground as my multi-meter wont read that fast. Guessing a test light is in order?

I highly doubt that 4 COP all failed at once, or 4 injectors failed at once.

I also looked for a fuel pump driver module...nope none to be found.

I dont want to drive this thing and kill the cat on it. So at this point Im stumped. It almost seems like either a coil driver or injector driver issue in the pcm?


Please help

 

***tumbleweeds?***

 

How's your voltage?

 

12V on both the injector and COP rail. Injectors are pulsing, can feel them clicking.

Now it gets even wierder. Fired the truck up yesterday and it ran a lot better. I did NOTHING to it. After it started warming up, it steadily got worse. Unplugging any of the injectors or coil packs yeilds a rougher idle now. Im going to pull all the injectors today and see if a sonic cleaner may make a difference. Also have to inspect the fuel rails for flaking plating.

 

what year is this?

 

Since 7 and 8 are throwing a code you might've blown the head gasket between them. Do a compression or leak down test at least on 7 and 8.

 

Its a 2007. Going to pull all the injectors out shortly and make sure they are clean and the rail is clean. I cannot get it to throw a misfire code now, but it still running rough, shaking at idle once its warmed up.

 

Interesting coincidence that 7 follows 3 and 8 follows 4 in the firing order - 1-3-7-2-6-5-4-8.
Not quite sure what that could mean.

 

Hmm....well that could actually mean a lot. Since there are 2 cam sensors and fire timing is based off of them and the phaser "tangs"....

Im starting to wonder if its slipped a tooth on a cam. Will put injectors back in tonight and if its still running bad, going to do a compression test.

 

Changed the fuel filter, sonic cleaned all the injectors...no dice and now it will NOT throw a misfire code. Im pretty sure I know whats happened though. I believe upon startup it jumped a tooth on one of the timing gears. Going to take it to a shop that has the ford IDS? type hardware/software and read the phasers and look for cam sync.

Anyone know where to score a set of chains, buffers, and phasers for less than an arm and leg?

 

Well cam timing is spot on....however power balance shows #8 is just about completely dead. pcm is trying to compensate with #4. #7 is also weak and #3 is trying to compensate. At least thats what the guy reading the bizzare graph stated. I did not put the injectors back in the same holes they came out of, so I know its not the injectors. After driving it a bit, its now showing P0171 lean bank 1. Not sure what thats about Looks like a compression test is up next. Hoping its a broke valve spring/springs or a head gasket. That will be the easiest to fix.

 

Well found the problem...couldnt be worse news.

Pulled the valve cover, all looks normal. Put a new plug in it for giggles, now it makes a popping but its not in the exhaust or intake. Did a compression test.....moves the needle about 1/8" on the gauge... not even 1#. Thought my gauge was screwy so put on 5= 168#, 7=170#

So its not the head gasket. Pretty sure its craterd a piston. Going to button this thing back up and offload it somewhere for a diesel.

 

The test you did is inconclusive. You need to do a leak down test to know for sure.

 

I rolled motor over to tdc on # 8 with both valves closed and it will hold absolutely NO pressure. I can feel air coming out of the drain back holes in the head when I pressurize the cylinder.

 

Well truck will be going into a shop next week for a ford reman motor. Roughly $6500 round trip....ouch. Still cheaper than a 5yr car payment LOL!