Misfire and spark plug recommendations.

[Brad Morrissette]

I recently picked up an 08 Eddie Bauer with 132k on the clock. Immaculate interior for 4K. Engine has a misfire on cylinder 8, causes the stutter/ hesitation or if I punch it a flashing CEL. Hoping it’s the plugs and coil boots rather than timing, but will do that if necessary. What plugs does everyone recommend? I have seen some people using the updated motorcraft plugs.

 

[Thunderbirdsport]

Plugs, and if still an issue, swap coils till you find the problematic one(s). Mine did this too, I threw on new plugs and no more issues. I used the Sp509, though mine is an '11....

 

[Trainmaster]

Ford Motorcraft plugs. The 2008's with engine dates on the right valve cover built on or after 10/9/07 do not have the problematic "two-piece" sparkplugs.

 

[Brad Morrissette]

Ford Motorcraft plugs. The 2008's with engine dates on the right valve cover built on or after 10/9/07 do not have the problematic "two-piece" sparkplugs.

That is great to know. Thank you. Will check when I get home

 

[RobE]

The hesitation is most likely the spark plugs. There is a technique to getting out the old design plugs so as not to break them off. I had a 2007 Expedition with the faulty design and used the TSB technique and didn't have one break. http://www.brokensparkplug.com/TSB_08-7-6_Pg1.pdf

 

[Brad Morrissette]

Ford Motorcraft plugs. The 2008's with engine dates on the right valve cover built on or after 10/9/07 do not have the problematic "two-piece" sparkplugs.

Just looked a little bit ago. Assuming it’s the printed label on the drivers side valve cover it looks like 11/27/07.

 

[10Expedition]

You could be describing my 2010 Expedition. Same miss and same CEL. Took it to the dealer because my local mechanic wasn't sure he could fix it. They first changed the camshaft timing control solenoid valves. Didn't fix it even though the computer said they were defective. Changed the coil on the #8 cylinder and all spark plugs and is now running perfect.

 

[Dustin Gebhardt]

Plugs are an "easy" solution. Getting at the rear plugs (4 and 8) can be a chore, but not impossible.

 

[Thunderbirdsport]

You could be describing my 2010 Expedition. Same miss and same CEL. Took it to the dealer because my local mechanic wasn't sure he could fix it. They first changed the camshaft timing control solenoid valves. Didn't fix it even though the computer said they were defective. Changed the coil on the #8 cylinder and all spark plugs and is now running perfect.

Hopefully they only got you for the coil and plugs? Misfire are almost always bad plugs, then coils.
The other stuff is a lot less likely to cause misfires, if at all.

 

[Brad Morrissette]

Cylinder 8 I just replaced plugs on bank 2, and the coil on cylinder 8. Runs more ch better now, will get bank 1 done tomorrow

 

[RobE]

Cylinder 8 I just replaced plugs on bank 2, and the coil on cylinder 8. Runs more ch better now, will get bank 1 done tomorrow

Yep, look at the gap on the used plug. That would definitely cause a misfire.