I drove diesel-powered pickups and SUVs for years before buying a 2015 F-150 with the 3.5 EB, which is my first gasser in a decade. The diesels all idled like the proverbial sewing machine, but the EB idles--as best I can describe it--with a faint stutter. I can feel it through the seats, but I can't feel it when putting my hand on the engine cover, and the engine itself doesn't vibrate on its mounts. We fired up another 3.5 on the lot and it did the same thing. The A/C was off in both cases.

Is this normal for the 3.5? I have no way of comparing with other truck engines because all of my recent experience is with the oil burners.

 

No. The ones I tested were all .... sewing machines, lol.

Check yer plug gaps fer a start. No higher than 0.032, stock.

MGD

 

I could barely hear my '12 3.5 EB when it was running. When you gave it gas, you almost heard it get mad. I called THAT an 'angry sewing machine'.

I much prefer the rumble of my '15 5.0L V8 ...

 

Can't ague with that. Angry bumble-bee, lol.

And the 5.0 is music above 4,000 rpm. Sweet fayncy Moses!!!

MGD

 

Mine does the same thing. Only felt at idle. I suspect the fuel system needs cleaning but don't really know. It's going to the dealer next week. We'll see what they say. More to follow.

 

Let us know. Mine still "quivers" at idle every few seconds.

And thanks for searching out the original 2015 thread and adding to it, rather than starting a new one.

 

Mine has this same roughness at idle. I actually reported it at my last visit to the dealer, who (contain your surprise) said it was normal. It isn't something that seems too crazy or anything, but definitely noticeable if I'm paying attention.

Interested to hear if you get anything different back.