help with sensor identification. *URGENT*

[TNR]

2000 ford 4.0 SHOC

Replaced sensor on block (IAC?)

Did plugs and wires.. truck starts, but idles around 2500 - 3000.

Can someone please identify what the sensors are along the intake air hose?
I know the MAS But further down the line there is a small sensor with a little slotted dial in it. It matches up with a slot in the head/air tube. When I remove this sensor, the engine idles normal, but the throttle is sticky/surging.

When you take the sensor off and manually turn the slot inside the airtube/head with a screw driver the idle changes and you can hear a flapper or something in there moving. Almost like Manually tweaking the throttle linkage hard. Is this some sort of a throttle control/regulator for the engine warmup or something? Or maybe some sort of Air Tempature sensor that also controls the throttle based on engine temp?

If someone could map the the sensors in this engine, or lead me to a source, I searched the board but if it's there, I couldn't seem to hit the correct search pattern.

As it is now, this thing is technically undriveable. It nearly surged us into the back of another car today!

TIA!

 

[410Fortune]

The sensor upstream of the MAS but before the TB is the intake air tempature sensor.
When you remove it you are creating a leak in the intake, or air coming into the throttle body the MAS did not measure, so it will throw off your idle.

When you replaced your IAC??? (IAC is on top of th eupper intake manifold) did you re-set the computer?

 

[alexefron]

IAC is on the side of the throttle body (drivers side). and yes did you reset the computer?

 

[410Fortune]

the IAC is not on the TB on the SOHC 4.0L, it is on top of the plastic upper intake under the cosmetic SOHC shroud.

 

[alexefron]

oh duh. i read 91, didnt notice the first line of his post.

 

[TNR]

Reset the computer...

Thing runs perfectly again, no throttle stick, or hesitation!

Thanks!