Spark plug OEM FORD or AC DELCO

AC Delco double platinum spark plugs belong in that engine.

I went 134,000 miles on a set of spark plugs on my 11 Ford Fiesta which is, what, a bit around 215,000 km? They were still in decent shape when I pulled them, just a bit out of gap spec, and I was still getting really good fuel mileage.

I use them. Just replaced a set after they'd lasted 90,000 miles, only to rule out a very very tiny misfire count issue I've noticed lately. I might get a coil pack now, but those original plugs surely would have lasted longer (they say they should last for 100k).

Had to replace the plugs and ignition coils last summer and that fixed it.

I replaced them with AC Delco 14 Platinums, and it seems to be running better.

Just did mine with ac Delco, gapped them in advance and running great!

I bought six ac delco spark plugs from Rockauto and half were made in France and half were made in the US. There are very slight differences like the diameter of the electrode and how deep the plug is on the end that goes into the cylinder. Even one of the US plugs is different from the other two.

ditch the delco plugs, they are trash. And delcos are shit plugs.

I own one of these, and I couldn't have a lower opinion of Fords engineering (the 2v spits out spark plugs? lets "fix" it on the 3v and make it so they will never come out).

My 6.0 never ran right unless I used AC Delco. And specifically whatever the current equivalent part number is to what the manual says.