Having this pesky high idle on the Ford. I am driving a 1998 Ranger 4.0L V6 5 speed manual.
I think i've gotten the vacuum hoses all sorted out and fixed.
So when it's warm and I am driving with no temp controls on it produces a high hanging idle. When coming to a stop light, I'll push in the clutch and put it in gear. when I come to a complete stop, idle is at 2000. i tap the throttle and it drops to about 1200 right away and then down to about 1000. It feels like something is sticking.
I disassembled the cruise cable from the throttle cable thinking that could be part of it. Nope. Cruise hasn't worked since I got the truck, but its not something I really need.
I sprayed lube on both ends of the throttle cable and also the springs connecting the cable assembly to the throttle body.
I have cleaned the Maf with Maf cleaner and taken the front off the throttle body and cleaned inside.
I have Cleaned the pcv and hose.
Not sure if it just needs a tune up or what it could be.

 

Still encountering the same issues. except now, the truck wants to idle at 1500 consistently at red lights. even tapping the pedal doesn't get the idle to pop down.
I have also started to experience a very rough idle recently. This is a first. I'll leave the truck running to warm up and it will sputter down to about 100-200 rpms and almost stall before catching itself and idling "normal"
Can anyone chime in here and tell me where to look?
Thanks.

 

Clean the IAC(idle air control) Valve as next step

Read here: How to: - IAC valve cleaning thread (w/pics) | Ford Explorer and Ford Ranger Forums - Serious Explorations

Also replace ECT(engine coolant temp) sensor, NOT Sender
Computer sets idle using the IAC Valve, and it bases the idle RPMs on coolant temperature, which it gets from the ECT sensor.

ECT Sender is only for dash board temp gauge

You can test ECT sensor with volt or ohm meter, but at $10 it is just easier to replace it on spec.

 

I cleaned the IAC today.
I did replace the TPS sensor a couple days ago.
Replaced...or attempted to replace the ECT "sensor", but made the mistake of the taking out the "sender" instead. So I fixed my mistake and hey...all of a sudden the gauge worked again in the Instrument panel. lol.
I am a little confused. So is the sender slightly to the left of the thermostat tube, with a one wire-brown connector?
The sensor, I think, is just under the throttle body on the engine. its a two wire-grey connector with a gray/red and green/white wire? I took this out and cleaned it. the male end that goes into the engine has a different end than the one I bought. Not sure if I got the correct one or not.
I'll have to do some more research on it and make sure I buy the right part.

 

Sender is only used by dash temp gauge, it can have just 1 wire, some have 2, but 2nd wire is just a ground which can be done via thread connection on the intake manifold, so only 1 wire is needed.

Sensor is only used by computer, it must have 2 wires

Senders end will look like a Cylinder
Sensors end will look like a Cone

They are not interchangeable, they have different circuits inside

 

So I found another broken vacuum hose and replaced it. Replaced the PCV valve. and then sprayed brake cleaner in small amounts around the intake. I did get a rise in RPM's when I sprayed around the EGR valve. I have the new valve, but have been at a loss on how to get it off. it is probably the original valve and heat welded on by now.
Is it easier to replace the whole EGR pipe assembly or just try some parts blaster and try working the nut loose? Also, which was does the nut go, clockwise or counter clockwise?

 

Lefty loosy
Righty tighty
Nothing special about EGR nuts and bolts

Yes, they can be very hard to get off.
Up to you really, if you can't get the tube off the EGR Valve then yes take it off the manifold

Use correct size wrench
But if you can get a pipe wrench on it it might help break it loose