I bought a used 2009 Ford F-150 XLT 4x4, 5.4L 3V Triton with roughly 90K miles on it two years ago. I’ve been driving it for roughly 35K mile since that time of which it's since developed a pretty bad misfire while driving. The current mileage now sits is at 125K miles.

I have replaced two O2 sensors due to codes that popped up for them because it was running rough. With that said there are no new codes have appeared on the code reader. What I do get is a check engine light that comes on and blinks randomly while driving. This same light will extinguish itself once the vehicle is slowed at idle for a stop light or after putting it in park. Not really sure how to interpret what the vehicle is trying to convey to me. I'm assuming its time for a tune-up?

I just bought the newest version of the Motorcraft spark plugs and will be installing them shortly. I was just pricing the ignition coils from Motorcraft and my jaw about hit the floor with the prices for it! Being that it’s not giving me a hard misfire code is it wise to only replace the spark plugs and use a wait and see approach to see if it resolves the issue? If I do replace the ignition coils…anyone have any luck with Delphi or other such brands?

Additionally, I know this engine had timing system issues related to the cam phasers. Anyone have any thoughts as to what the approximate mileage would be as to when I should start thinking about changing the items associated with that?

Would sure appreciate any inputs that may help.

 

The truck is giving you something worse than a hard fault. The flashing check engine light of death as its known. By the time that light flashes you are already misfiring severely and dumping raw fuel and melting the cats. Flashing CEL = Pull over immediately and tow it. The coils don't need to be changed unless they fail. The boots and spri gs should be changed when plugs are changed. I wouldn't be driving this truck until its fixed, hopefully you didn't melt the cats already.

 

After you have changed your plugs, boots and springs, run your truck the way you did when the CEL started flashing. No CEL means you most likely solved your problem. If the CEL flashes again, then you need to pull a code to see which cylinder(s) is misfiring.

If you need coils and are hell bent to have the MC name, look on Ebay, they are sold in an eight pack for much less money than the dealer wants. If that doesn't work and you are bent on MC coils, then check out Tasca, still much cheaper than the dealer.

 

Thanks for the reply I haven't yet checked e-bay for MC ignion coils but I will soon.
It's not that I'm hell bent on buying the MC brand specifically just not familar with ignition coils in general.
So, with that said I was in part defualting to Fords MC brand.
It's just that in reading various web sites it seems as though it was the go to product with the least issues?

You have other brand recommendations?

 

Many members here are diehard MC parts people and there's not a thing wrong with that if you have deep enough pockets.

I have no clue as to who makes MC coils though I've looked the boards over. Still nothing. So, if it's that big of a secret then the brand must not matter.

I've never heard anything negative about Delphi.

In fact, two years ago I replaced all eight in my 2004 Expedition with Autozone gold coils and spent a fraction of the money. They are warrantied for life BTW.

The point is, on a truck with 125K on the clock, is it wise to spend $800+ bucks on coils?