06 Focus 2.0 Very high rpm at idle, need help just cannot fix!

[craigndee]

Hello everyone. New member to the forum here already found some great information but need some help. 06 Focus sw 2.0 when started the idle goes right up to 2300-2500 rpm. It kind of stays there, comedown a little then creeps back up again. IF I blip the throttle it goes to say 4000 rpm and hangs there, screaming. LOL then it starts to make its way back down to the 2-2500 range again very slowly. Have tried throttle body clean, new IAC valve, new TPS, replaced pcv hose and valve, new intake gaskets, valve cover gaskets and spark plugs. The car blows from the oil cap and does plum gray smoke, not white. When I replaced the pcv hose I checked and all tumble flaps on the manifold they look and operate fine. Checked the vac lines to the intake runner actuator all good and I have visibly seem the actuator move. If I start, put in drive without touching the gas, the car will do 35mph. lol Of course the motor mounts are shot and have those to go in once I get this thing running correctly. Anyone ever come across this before? I'm starting to think the computer is to blame and am pretty tired of throwing parts at this. Any help greatly appreciated guys!

 

[Handy Andy]

This can be from a variety of things...

Ran a Code scanner tool in the DTC connector to review or even check for pending DTC's?

Oil Level ok?

Coolant bottle ok? Color clear and clean or dark n dirty - oily?

Do this...
While getting into your car, locate the left side OK and menu arrow buttons on the steering wheel - You can hold the Left side OK button on the steering wheel and enter into "TEST" mode and using the OK Up and Down buttons can scroll thru various test "stages" including "Voltage Test" and see if the voltage from the battery is holding up.

To do that, you Press and HOLD left side OK down (in or whatever) and insert key turn it to Ignition (On) - don't start it yet. Hold the OK in until your menu displays "TEST" - then you can let it go - release it - and let it perform a boot into self test mode - then use the Up or Down arrow on the Left Side OK - and you'll see it scrolls thru various stages or test results - you can also start the car at this time - but scroll to find "Battery Voltage" first - and look at those results - then start the car and see if the voltage can rise fast enough - if it's slow to rise, then you may have to get down and dirty and start cleaning grounding points - they may be corroded or as I have found - several wires in a bundle sent to ground - have broken away or literally have had the copper in the wire corroded away from the lug holding it to the grounding bolt.

Then you have to strip the wire and resolder it back onto the harness lug so it can make ground again.

That is if you have such a means, if not, then you'll have to use a DVM (Multi-tester) and run a "battery monitor" test (check voltage) using the DVM and even do resistance checks from the Throttle Body connector to ground - find the lowest ohmic reading value one, the one that Grounds (provides Return) for the Throttle body, it's supposed to be less than one ohm - measured to the battery or frame ground - it could be that the grounding point wire, in any bundle from the harness that grounds at various locations - has failed and is why you're seeing such a high idle because it can't "see" any true voltage reference across itself to "zero" the electronics so it knows where the throttle is set.