I own a 2002 FX4 with a manual tranny and I was wondering if anyone else was having the same problems as me. First of all when I'm decelerating (foot on the clutch, or in neutral) the engine does not go down to the proper idle speed which is about 1,000 rpms(while moving). It is almost like the computer doesn't "catch" it in time, it will either go down to 300-400 rpms. Sometimes the it will on ly drop down to 600-800 then go back up to 1000-900 rpms. Also occaisonally I will push the clutch in and the rpms wont even drop, it will stay there for a moment and drop ever so slowly. The engine idles fine if your just sitting there. It is so inconsistent that Ford can't nail it down. I don't think it is the way I drive because every truck I've owned has been a manual and I never had a problem with them.

My second problem involves the power steering. When I'm just sitting still and I barely turn the wheel and the engines bogs down a couple hundred rpms. Sometimes it is more subtle it will only drop about 50 or so. There is also a hydraulic pressure sound. All of this is with the accessories(A/C etc.) off. Any feedback would be appreciated.

 

Sounds to me like there is a problem with the computer....engine management system, throttle position sensor, something.....

 

My first guess also would have been the TPS and/or related servo idle speed controller. But if Ford can't nail down something that simple, it sounds to me also like computer, or a sending unit / sensor problem. The power steering COULD be a separate issue. If the internal hydraulic pressure is getting too high for some reason (producing the hydraulic noise you heard), I could see how that combined with your idle speed problem could cause significant difficulties with idle speed. Too many daggon controls in 21st century vehicles for a shade tree mechanic. GOOD LUCK!!

 

I really hope you find out what that is because my best friend has a 99 F150 4.6 5sp 2wd that has done this(idle dropping to low when slowing down)since it had about 20K miles. He bought the truck new BTW. His truck has over 100,000 and still does it. He had it to 5 or 6 different service depts. and it was never fixed for more than a couple of weeks until it started again. It's funny he loves the truck, and NOTHING has ever broken or messed up except that one quirk that won't/can't be fixed. If you find out anything please post.

FYI, when he took his truck in they would always replace a 02 sensor(not always the same one either) and the problem would go away for a few days or weeks)

 

sounds like an IDLE AIR CONTROL VAVLE situation to me. take it off and clean it with some cleaner.

 

i know that on my 99 superduty and my 02 crown vic (both autos) when you are traveling down the road and shift into nuetral the rpms go up to 1500 or so. i believe it has something to do with maintaining brake pressure or something.