So I'm coming home tonight, and I got on it once pretty good, and then a little when I got toward home. When I slowed down I felt it jumping a little. No sounds, no detonation, nothing like that. Just a rough idle.

What do you all suggest, check the plugs first I guess, coilpacks, and IAC??

At first I thought it was my tranny, because it's rougher in gear, but I think that's just because it lowers the RPM's, I can hear a SLIGHT misfire at tip in from low RPM. Like a little pop. Other than that, runs fine. Didn't really get in it too much once I noticed the problem.

NOT in the mood to mess with any of this, but oh well....

 

I started again this morning, and it's still a little rough, but ONLY at idle that I can tell. When I cold started and it went right to about 1000-1100 RPM there was no vibration....It seems like the IAC, but I can smell raw fuel, so I'm guessing, one is not firing off correctly.

Will scanning it let me know??

 

I've been trying to fix that problem for years now. While under warranty, the dealer tried many things.. from the IAC to mass air meter, to what they called a "recalibration of the computer." It got a little better when I got the Denso's in but it still does it. Its a slight rough idle that goes away if you lift the RPM's ever so slightly.

Its really annoying and its worse in the winter for some reason

Jon

 

Mine has never done this, so I don't forsee me leaving it this way. I guess I'll pull the plugs and check them....my gut is it's a coilpack or something else though.

 

If its a coil pack it will almost feel like the trany is shifting wrong.... my company van had that problem, the idle was ruff...but not THAT ruff....when I got between 35-60 mph it would feel like it was dropping in and out of gear... really odd... but it is perfect again after replacing it.

 

WaveBlaster785:

I've had the rough/twitchy/choppy/irradic idle for about a half year or so. It all started when I had new plugs put in (warranty fix at ~24k miles) plus IAC & mass.
Shortly after that, the truck "developed" the rough idle (only at idle, runs fine beyond idle)...two dealerships ran the typical diagnostics and NO error codes shown even though you can SEE and FEEL this rough idle...both dealerships said we can't fix what what shows no error codes. The L has had about 4 diagnostic runs and it always comes up as "no problems shown". So I pretty much gave up and I hope you have better luck than me. I still feel that coil packs can be marginally bad and NOT show up in diagnostics or throws an error code. My warranty ends in 2 months and this may be my last Ford vehicle. Good luck to you.

 

I pulled my plugs tonight and my new plugs should be here tomorrow.

One plug was broken and completely wet, so with any luck that is the problem The electrode was worn away and the ceramic was cracked.

I'll find out tomorrow when I put the new plugs in if that was the issue. The rest of the plugs were fine, but for a couple dollars I might as well replace them while they are out.

Thanks everyone for your input, and a big to Sal for his help on IM.

 

Probably was the plug. I had the same problem and when Johnny Lightning
pulled my plugs before dyno tuning one plug was missing an electrode. Put in a
new plug and the problem went away. Hopefully the new tune will eliminate
the problem.

The Ghead.