Pout pout pout I am sad

[Jeffintampa]

Well shoot, I have got a bad miss in my 4.6 in my o2 xlt. New coils compress tests etc show the front driver side (closest to the grill) is missing. Bad valve, bad rings, not sure what, like half the compression the others have, Now maybe this will tell some of you what it could be, For about the past year and a half when I would start it I would get a big puff of blue smoke, not smoke while driving it just on cold start Stopped doing that and started missing,

estimates are
1200.00 to pull head and reinstall
200-400 valve job
150 gasket kit

or
1000.00 to pull motor and install different
1200-1400 different 4.6

 

[toms89]

Add tablespoon of oil in that cylinder and redo compression test. If compression goes up its the rings. No change means bad valve or mechanical failure. Puff of smoke could be valve guide(s)/ seals leaking oil into cylinder when it sits. This would seem to indicate valve issues

 

[sgtowing]

I would say valve seals. oil drains down after sitting and when you start it, ****, oil gets burned and no more smoke untill you shut it off. maybe think about V10, cummins or PSD swap.

 

[dougmcp]

It may not be rings or valves, these motors are notorious for bad head gaskets.
You can do a pressure test on the cylinder to confirm.

 

[Jeffintampa]

Thanks guys, the cyclinder has half of what the others have in compression, I will try the tablespoon of oil and see what that does great tip thank you. My kids drive the expedition most of the time, and they run the gas on fumes almost always, I preach about the crap in the bottom of the tank,

I think it is the valve seals, I have tried sea foam no help, same studder while setting at a stop light

 

[Jeffintampa]

Had a retired mechanic try to fix the miss and he said its only got like 70 psi in the number 5 where the rest have 180 he said major tear down to repair

 

[CARO'S98EB]

It does sound like a major teardown at least the head off. As for the head gasket I have worked at ford dealers since 95 and I have never had a bad head gasket on a 4.6 in anything. the only head gaskets on a ford v8 that had problems were a few 99 5.4 and that was for a oil leak between the head and the block.

 

[hwy73]

It does sound like a major teardown at least the head off. As for the head gasket I have worked at ford dealers since 95 and I have never had a bad head gasket on a 4.6 in anything. the only head gaskets on a ford v8 that had problems were a few 99 5.4 and that was for a oil leak between the head and the block.

My 99 4.6 is on its 3rd head gasket for that oil leak on the passenger side. First time under regular warranty, Ford told the dealer to replace the engine without even a teardown. Next 2 they dinged me $100 deductible under my extended warranty to replace gasket, and it's leaking again.
Hijack off.