5.4 with morning time grumble
 

I'm assuming I might have a coil going but I'm not sure. Yesterday morning and this morning I started my truck and it was fine, I backed out the driveway again truck was fine. I put it into D and pull forward it was fine till I hit about 1300rpm, then it felt trike the truck was stumbling, I went a little faster to 1500/1600rpm and it stopped, as soon as I slowed up and then hit the go pedal it started again at around 1300rpm and stayed till 1600rpm and then it went away. So this is twice now two days in a row this has happened the exact way and only in the morning and goes away with no problems. I hooked up my SCT X3 and there are no codes and when it stumbles I have no lights come up. Any ideas on what I should do?

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Sounds that way to me. Not sure how many miles on your plugs but they need to be changed after 100k. Your cop boots start to crack and "leak" pulses out to the plug hole walls, giving you a random misfire for that cylinder.
If I drive my 5.4 hard, it will pull a code which sure helps to identify the exact cylinder.
You might just order boots and change out, whether with or without plugs.

Bought the truck brand new, I install motorcraft plugs ever 30k and COP boots ever 40ish. I have 133k now and just did new plugs and COP boots this September

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Ok two days with no issues...what the heck is going on with my truck?

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Mine will do that once in a while if we get a lot of rain, I say drive it until it throws a code then you will know the offending cylinder :-X22

Check to see that you don't have an intake manifold leak, allowing coolant into the plug hole to help ground out the COP randomly.

It didn't rain the first day but the second morning it was pouring when it happened, and since then nothing so I'll keep an eye on it I suppose

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Double check all of your COP-to-harness connections. I did plugs/boots/COPs not long ago and things were fine for quite a while. Then I started experiencing issues similar to yours. When I investigated, I found that I didn't have two of the COP connectors fully seated. Been problem free ever since.

O-rings on the COP boots may help. See link below. Otherwise maybe time to clean the IACV.

https://www.ford-trucks.com/forums/1...s-the-fix.html

Kind of a similar issue that im investigating now

That doesn't mean your new parts are not malfunctioning....

Thanks Bently I'll check this out later today

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Ok I checked the plugs and cop again and everything is dry, no water or rust present. I did the oring upgrade to the cop boots and truck has been fine, last night it poured for about an hour. Get up this morning to leave for work, back out the drive way truck is fine put her in Drive go about forty feet then BAM at a steady 10mph the truck does the death shake! This time I keep my foot exactly still holding ten mph and truck shook like crazy, about seventy yards truck smoothed right out. I stopped turned around and went home and removed the two back cop on the passenger side where the water runs into the plug holes and both were absolutely dry again with no sign of water. So what now? Truck is throwing no codes or dash lights so do I keep letting this at random engine stumble go until one day it just doesn't go away while I'm trying to go to work or bringing my kids somewhere?

Dont wait for it to throw codes I'll say that much. Pretty sure their programmed not to complain lol.

And if its doing a "death shake" Id wager you have more then 1 bad coil at this point, and unless you have some good spares you probably wont figure out which ones.

Yea I even pulled one cop connector at a time when It first happened to see if the motor would react different but at idle it never changed. And my second problem is it's been over a month since it happened last so my luck if I buy one new one it will take me a year to figure out what one is going bad LOL