TOO MANY REVS!!!!

[facemaze]

@RonD thanks for the heads up on the CHT. I had some raw wire on wire action above the sender.

I wasn’t able to get the truck started for a drive with the IAC removed as you suggested. Maybe I missed something.

after I patched the wires, I took it for another test drive. I behaved much better. I was able to move through alll the gears like normal, however after sustained rpms above 2500 in fifth I’d I engage the clutch and shift to neutral and the rpms would stay above 2500 for a minute or two before returning to a normal idle. I was able to replicate this once in 2nd gear but no other gear.

could my accelerator or cable be malfunctioning.

also ran an OED with no codes.

 

[RonD]

You have to push down on gas pedal a bit to let air in when starting engine without IAC Valve plugged in, IAC Valve opens all the way to let in air for start up
And you need to do the test with engine already warmed up as before.

You can pull off the air tube from intake and check if throttle plate is loose or sticking, longshot

PCV Valve is a "controlled" vacuum leak, Ford recommends replacing these once a year on the 2.3ls but its a pain on these engines
Its "possible" the PCV Valve is sticking open, but also a longshot
You have to go thru drivers side wheel well to access the PCV valve on the 2.3l duratec

 

[facemaze]

I’ve changed a PCV and yes it’s a pain. I did change mine last year or so.

Ill give the IAC a try again.

 

[facemaze]

@RonD

just did the drive without IAC and had no problems with the rpms dropping upon engaging clutch.

could this mean the IAC is bad?

 

[RonD]

Yes, could be but most likely a computer issue
Its possible the IAC Valve it sticking open at a certain spot so there is a delay when computer tells it to close and it hangs up for a bit
Its just a spring loaded solenoid, spring holds it closed, computer sends 7 to 11 volts via ground wire(PWM) to pull it open and hold it open, then as computer reduces voltage the SPRING should push it closed to match lower voltage, unless it sticks..........

If you want to clean the IAC Valve you can try that
If you want to replace it then only use Motorcraft or Hitachi brand as replacement, other brands will cause similar or other issues

Info on cleaning an IAC Valve here: https://www.explorerforum.com/forums/threads/iac-valve-cleaning-thread-w-pics.84220/
Different type that yours but cleaning them is all the same

 

[facemaze]

@RonD
Well i gave the IAC a good cleaning and replaced the throttle body gasket. took it for a test drive and there were no issues with the rpm's. it acted as normal.

However my temp guage on the dash stayed very low and the bluetooth oed scanner said my ECT was -40 c. Got home and ran a test. Through the code for the bad CHT. so im gonna replace it.

Am I on the right track?

also, I did find a leak where that tiny tube connects to the under side of the intake manifold right below the throttle cable by about 4-5inches. What is that tube?

 

[RonD]

Yes, for the CHT, replace it, need a DEEP socket

Dash temp gauge uses a separate SENDER on the engine

 

[facemaze]

@RonD thanks for all the help. It’s up and running smoother than it ever has.

 

[Uncle Gump]

@RonD is really all of our Ranger Hero...

 

[kaltertod]

Having the Same issues here,

1995 Ranger
4.0L
207k miles

Parts Replaced:

Fuel Injectors
Fuel Pressure Regulator
MAF
IAC
EGR
Intake Gaskets
ECM
DPFE Hoses
EGR Piping
Coolant Temp Sensor

No vacuum Leaks, Engine Idles at 500 RPM With IAC unplugged, Engine temp reads correctly using a scanguage. Cleaned and reattached all grounds to engine/body.

When I start the truck the engine revs up to about 2k rpms and then settles down to about 1200-1500 rpm until the truck reaches operating temp. Then the truck will idles just under 1k. If I depress clutch while driving the truck to shift gears it will rev and hold a higher rpm for a few seconds then will drop down to 1500 rpm. If I come to a stop the idle will drop below 1k.

Getting frustrated any help would be appreciated.