High Idle Speed

I own a 2006 Ford Focus ZXW 2.0 L DOHC 5 SPD STD with 67 K miles.

When the car is not moving, the idle speed is around 900 rpm. When the car is moving at any speed, the idle speed does not drop below 2200 rpm. When the car comes to a rest, the idle speed drops back down to 900 rpm.

What could be causing this problem??


You’ll need to be more descriptive. You sit at a stop sign with the clutch in, car in first gear, and the rpms are about 900? You start out from the stop - the rpms will rise with speed until you shift. You push in the clutch and just let the car coast - and the rpms do what? Or say you’re in 5th gear at about 60mph, you push in the clutch - what happens to the rpms? It is implausible to assume that the car remains at 2200rpms and then just drops to 900 as soon as you come to a stop.

How experienced are you with a manual transmission? The rpms have everything to do with the gear you’re in given whatever the speed of the car is.

I should reply with a preface. The gas pedal was sticking everytime you pushed on it. To remedy this, I lightly cleaned the throttle plate to remove residue build up. The pedal worked great, but then the idle spped issue came up.

When I first start the car, the car idles high until it warms up then drops to about 800 - 900 rpm. That, I understand, is normal.

However, once I start going down the road I can coast with the trasnmission in neutral, and the idle speed stays about 2100 rpm. When still in gear, the car will nor slow down on its own when I let off the gas pedal. It wasn’t doing this prior to my cleaning the throttle plate.

Once I come to a stop (either clutch pushed in or sitting in neutral) the idle speed will slowly go back to about 800 - 900 rpm (normal idle speed).

Thanks for looking into this.

I’m not sure what a light cleaning the throttle body is (I guess just spraying some TB cleaner into it). I would just pull the throttle body off and give it a thorough cleaning. If there is carbon build up causing the plate to stick the bulk of it is probably on the inside. Just use a throttle body-safe cleaner and some soft rags so that you don’t kill the coating. While you have that off you might as well clean the idle air control valve is so equipped.

You’d also need to check for binding and that the return spring is ok. Is this a cable controlled throttle or drive by wire? (I don’t know what year the Focus changed over). Check out all of the linkage for any kind of binding points.

If a thorough throttle body cleaning & linkage check doesn’t yield anything I’d want to watch the throttle position sensor on a scantool.

Funny your should say, but I’ve aleady removed the throttle boby and cleaned it as well as the Idle air valve. I also replaced both gaskets and I replaced the throttle position sensor since it wasn’t that expensive. Maybe there is a setting that I overlooked.

I read in a Hayne’s manual that there is a coating on the throttle body. What kind of coating is it and, if I’ve screwed it up, will that affect the kind of problem that I’m having?

Thanks again.

The coating on the throttle body should be teflon. I would think it’s possible that cleaning with chemicals could have removed some of the teflon, which in turn could possibly create a vacuum leak. Of course a vac leak will increase rpm. It’s kind of a puzzler, with the rpm staying at 2200 while driving, and normal idle at a stop. Makes me believe that somehow the speed sensor voltage while moving, is interfering with something else. Like maybe tps, or maf voltage.

Doesn’t sound like a classical vacumm leak issue. That’s why I sent out a comment on this website. I may be forced to take it to a Ford dealer and have a diagnostic done.