1995 ford f150 with 5.0 engine idling high - 1995 Ford F150 Styleside Regular Cab

OK, so is it still setting the codes? Or has that gone away with the transmission harness repair? The idle is controlled by the Idle Air Control (IAC) solenoid. Ford has had a lot of trouble with these. However, the symptom is usually low idle speeds that cause the engine to stall. I think I would be looking for vacuum leaks. Ford 4.6L engines are notorious for the PCV hoses leaking at the elbow where it connects to the back of the throttle body.

Check your Idle air control valve or EGR valve, unplug egr valve and if it idles down and smooths out then replace it, if nothing changes I would consider replacing the IAC.

Did you install new spark plugs? Definitely replace the O2 sensor.

Intake manifold gasket is leaking. Its like you have the throttle open to let in more air. You can spray a jet of water around the manifold and when you hit the seam that is leaking while the engine is running, the RPM will change. Or you had a vacuum hose burn or fall off.

High CO usualy means the O2 sensors are not reading properly. Take it to a parts store that can read codes, I know Auto Zone does in my area. If it is the O2 sensor it is an easy fix but the sensors run about $50.00 each.

check the idle and adjust the idle.

In my 1996 ranger xl my high idle problem was due to a bad ect sensor. After I replaced that I have had no problems with high idle. Not sure if yours is idleing high all the time like mine was but that sensor fixed the problem for me. Hope this helps!

The IAC valve is usually the problem with the 1.9 Escorts ,causing a very poor engine idle at a stop. It is located on the side of the throttle body .

The Idle control Valve will not in most cases help you check for a vacuum leak that csuses High Idle in Taurus a lot check for the PCV hose.

Hi , i have a 1995 Escort with 1.9 4 cyl engine , at cold start the engine revs ok but as it get warmer it start to idle rought and die , with a scantool the o2 sensor always reed lean at idle , after checking fuel pressure , air mass meter , EGR valve , and potential vacuum leak at intake and hoses , its the PCV valve that give me that problem , as i remove the pipe with the valve there was a whissle noise comming from it , when i block the valve at its tip the whissle noise stop the engine revs smooter and the o2 reads normal , i replace the PCV and its idling good .