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Hey everyone
this is a 2005 e250 with 220,000 miles. It’s actually a 4.6 but we all know these engines are the same- and I’ve found the best engine knowldge-guys I. The V10 forum. It recently started throwing misfire codes. Intermittently the CEL would flash and the van was low on power. Looks like the piston is melted or deformed or something.
I couldn’t decipher up/down/left/right, but all the pistons on this van had this same thing. To me it appears like the lowest point (gravity-wise).
Posting on iPhone makes weird issues on this forum. Sorry for errors.
”best engine knowledge guys in the V10 forum”
so i changed all the spark plugs and boots and used plenty of dilectric grease. Cleared the codes and test drove it. It seems a bit low on power but I haven’t been familiar with this van because my employee usually drives it 99% of the time. I’m familiar with V10 grunt and obviously this van lacked that. So I don’t know if it’s fixed.
Weeks ago it was misfire cylinder 4 so I installed a new (cheap) Autolite. No complaints for a few days but then came back worse- misfire cylinder 2.
Upon removal of all all the plugs, #2 was dramatically worse than the others, so I am hopeful. (I’ll post pics of the old plugs soon).
I just looked at a 100 or so pictures of 4.6l pistons. I didn't find any with the same shape on it. It does look to me like it was manufactured with that dish in the edge. The nicks on the piston are a little concerning, but nothing I would worry about.
I just looked at a 100 or so pictures of 4.6l pistons. I didn't find any with the same shape on it. It does look to me like it was manufactured with that dish in the edge. The nicks on the piston are a little concerning, but nothing I would worry about.
I just spent ten min searching and all I can find is NEW pistons, and at that; only aftermarket brands. What did you find?
I wonder if Ford used 3-valve pistons in the 2-valve motors? I'm assuming your 4.6 is a 2-valve.
yes sir it’s a two valve.
Im concerned that the “shoulder” of the dish isn’t uniform. It has a rather “sharp” edge except that section. And it was every piston in the engine.
I just spent ten min searching and all I can find is NEW pistons, and at that; only aftermarket brands. What did you find?
I went into google and typed in "4.6l piston pictures". By far new pistons outnumbered the used pistons, but every once in a while there was a picture of a stock piston that had been removed during a rebuild. Only 1 or 2 looked anything like the shape of your piston. yes...kinda wierd
I ALWAYS recommend new coils.
Swapping plugs and boots gets you into these kind of issues.
Once the trouble cylinders have new coils, plugs, and maybe refurbished injectors than other issues can be addressed with more certainty.
I just got 2 misfire codes on one of my V10s. Put in two new Denso cois and boom, fixed. Could it have been boots? I guess but now I know it's fixed and don't have to worry.
FYI these motors will run fairly well with 1 cyl down. V10. Once 2 go it's noticable. I had a hard misfire on cyl 1 and a pending misfire code on cyl 6. No check engine light.
please do not attribute things I did not say to me. Those are your words....not mine.
I have seen much worse piston tops that still preform well. As long as there is good compression these pistons can still work.
I suspect since all cylinders look almost the same that this is a result of some type of carbon removal and little pieces of carbon detached and created hot spots and little dings......just my suspicion.
could also be a result of leaking injectors, though it's really is hard to tell.
