Of course, this isn't something I would have noticed BEFORE I bought the truck . . .

Anywho, did the idle change on these with the new drive by wire setup? It runs ppuuurrrfectly from the moment you give it throttle, but at idle it has what feels kinda like a miss, like the timing is advanced just a tad too much, or the idle rpms are so low it might stall, but never does. Runs the same when you put it in gear, no idleing down, or stumbling real bad like my older truck used to do. Nothing bad on the top end, A/C doesn't affect it. . .is this just the way it runs? I'll be honest, I've never owned or payed attention to the way a v8 runs Is this characteristis of the newer v8, or any v8?

BTW, most all of my searches yeilded info on the 5.4, so yes I did search first.

 

is it a slight lump in the idle once in a while? if so then it is a normal thing these modular enignes do. the 5.4 is a little worse , but does not seem to affect engine life.

 

How long is once in a while? A little bump every 2 average seconds? Best way I can describe it is like when I timed my I6 by hand. There was the sweet spot, where it ran so smooth you had to see the fan spin to know it was running. Then if you advanced, or retarded the timing just a little, it still ran fine, but it was a just noticably "rougher", and evry few seconds it was like one cylinder would miss a little, and the missing cylinders would alternate. . .make sense? you need to be touching the dash or wheel, or rest your arms on the rest to feel it.

If it is normal, then I can't wait to put an exhuast on it, it would sound so sswwweeeettttt Maybe I should stop worrying and just enjoy the truck . . .

 

yes that is normal. you really have to feel for it tho. it is normal of these enignes , also most smooth out with miles. my 5.4 went from that to smooth as silk about 10,000 miles latter.

 

Theres about 15,300 miles on this truck. Are all 4.6/5.4L engines like that? What did Ford do to make the idle like that? Emmissions, economy? Or was it just with the introduction of the new body style and drive by wire?

Thanks for replying, I'd hate to have to deal with engine problems this soon. I already lost the crap-shoot with the rear-end (though its ever so slight), so the thought of fualty ignition this soon was gettin' under my skin. Seriously, I just want to whip out the 1/2" and adjust the distributor, but can't

 

the idle is inherrent of the engine. ford did not design them to do that. they just seem to have a lump in idle. mine has smothed out for the most part. but if you really look for it there is a slight lump to be felt every few seconds.

 

My 01 has done this since I got it. According to Ford, it is a combination of camshaft duration and a lean (for emmisions) idle mixture. It has no adverse effect on the engine.
That's the same thing they told me when I questioned it on my 88 5.0 LX Stang when I bought it new. If it had an idle mixture adjustment like a carb, about 1/2 turn out would smooth it right out.
My 01 5.4L seems to be worse sometimes, but I've gotten so used to it, I hardly notice it anymore. It used to let me know it was running by the slightly rough idle, but my 40 series Flowmaster lets me know now.
I installed a Predator tune in mine, and it didn't effect it at all. Still the same as day 1.