2018 with Hesitation when Cold

Hesitation is common place. Don’t over think it. Every f-150 I have owned did it.

GCATX said:

Since you rarely drive it, may be a battery issue? I would slap a trickle charger on it overnight and see if it makes any difference on the first drive. May be that driving it for a while gets the voltage up to *****, then letting it sit for a few days is enough to cause an issue?

Maybe not, but easy enough to try.

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I'll give it a try, thx.

baugustine said:

Question: does it behave the same in NORMAL mode and SPORT mode?

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Normal

Yup my 2018 with 15k miles does the same thing... usually if I crank up and start driving without it warming up. Give it some light throttle out of the neighborhood and it falls flat on its face then back up. Doesn’t do it after that. Thought about taking it to the dealership.. but sounds to be a normal issue?

Cold combustion is less stable (unless optimised for in engines) due to less latent heat in the chamber aiding in burning of fuel, and on a cold start getting the catalytic converters hot is priority for emissions purposes (running low to negative timing slightly richer than stoich.)

I would assume phaser operation could be slow or intentionally delayed from cold oil not flowing as fast as hot to allow for cam timing as desired, and this could be what is felt.

New Nick at JDM said:

Cold combustion is less stable (unless optimised for in engines) due to less latent heat in the chamber aiding in burning of fuel, and on a cold start getting the catalytic converters hot is priority for emissions purposes (running low to negative timing slightly richer than stoich.)

I would assume phaser operation could be slow or intentionally delayed from cold oil not flowing as fast as hot to allow for cam timing as desired, and this could be what is felt.

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Just started doing it at 3k. Falls flat until I let off the throttle. Does that sound normal? Probably not safe if I was pulling out in traffic.

Its odd if it happens after time. I would invest in maybe new spark plugs and see if the old ones look abnormal.

New Nick at JDM said:

Its odd if it happens after time. I would invest in maybe new spark plugs and see if the old ones look abnormal.

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I'll give it a try. Cheap fix if it works. Thanks for your help.

It happens to my 2019. Like all the other posters, it happens just once when the engine is cold or partially warm then not again until the next time. It happens whether feathering the gas or driving normally (and no, I never hit the gas hard when it's cold). I believe it happened once when in Sport mode but I normally don't put a cold car is Sport mode. It's too jerky on deceleration when hot to begin with and seems worse when all the fluids are cold but I am going to try it to see if it happens in Sport when it's cold or partially warm.

It's ridiculous, unsafe and absolutely unacceptable. This is 2019 and everything in the engines today are computer controlled and digital. The whole point of this and phasers is to adjust timing, fuel etc for these moments so that this crap doesn't occur when cold or hot.

If all the computer corrections and technology that is put in these engines can't control a "pause" like this, then put everything back to carbs and mechanical levers that resulted in the same exact behavior 40 years ago. Ridiculous.

This has nothing to do with being a performance engine. I've had cars that perfom the same or much faster (BMW, Lexus, Toyota) and they don't make me feel like I'm in a 1974 carbed engine.

It's obvioulsy poor progamming that is responsible but you can't just take it to the dealer because it's not exactly repeatable and it doesn't throw a code because the computer thinks it's not doing anything wrong.

Has anyone taken it to the dealer and able to reproduce the issue for them and have it fixed?

Just because your engine idles to warm doesn’t mean your trans and diff fluids aren’t a thick soupy mess. It’s going to be a little rough until the whole drivetrain is warmed up a little