Alright, so I was in need of a FD IAC valve for the FD upper I purchased for my FC.

After looking around, basically I found used FD IAC's for $100 or so, and new ones for 200-300.

Then I found a 01-03 Ford Taurus IAC which looks really similar to the FD one. They're only $50 shipped new.
http://www.ebay.com/itm/SMP-STANDARD-AC239-F-I-Idle-Air-Control-Valve-/130913360409?pt=Motors_Car_Truck_Parts_Accessories&hash=item1e7b0b5a19&vxp=mtr
I ended up buying a used one for $15 shipped to make sure it would fit, and they do. They bolt up, but the Taurus valve uses circular ports instead of the FD's square ports. Which I don't think will be a problem but some testing is in order. The valve is a 2 wire model. It should work with many standalones, if not on the stock FD ECU.

 

Great find if it works! Do you know if the Taurus valve is PWM or a stepper motor type design?

 

Is the bolt pattern and flange the same though? Same number of wires, etc?

 

OEM Idle control valve is modulated by PCM ground with constant power supply therefore only two wires.

If it is a PWM idle air control valve, give it a test and I believe it should work. Great find if it is.

BTW, many mazda parts are interchangeable with Ford parts =].

-AzEKnightz

 

...this is a solution in search of a problem

lots of people delete the ISC valve. I'm surprised people are asking $100 on the classifieds here

 

The bolt pattern and flange are the same. But the Taurus valve does have round ports, while the FD has rectangle ports.

I have seen a couple of people looking for the idle valves, seems they fail every now and then or something.

 

Just because it's a two wire doesn't mean it will respond correctly to the OEM computer. You may have frequency problems with that valve. If the frequencys don't match, it may make an annoying buzzing sound. Let us know!

 

Ya... so far I'd only recommend trying this with a standalone that hopefully gives you control over the IAC frequency.

I really don't know what frequency the stock FD ECU puts out, you may have issues like you mentioned.

But like AzEKnightz else mentioned, Ford may have borrowed the design from Mazda, so there's a chance the frequency matches.

 

My old E39 540i BMW had an incorrect IAC fitted, and the thing buzzed its head off and was annoying. I know what you mean there.

Purely from an operational point of view, the IAC is just an electric motor that turns a cam, to cover or uncover a port, allowing additional air into the engine (or not) at idle. When the workings of it gum up with oil and carbon, you can usually unbolt them, spray carburetor cleaner or engine degreaser into the port of the IAC, shake it around til the flapper valve frees itself up, and then bolt it back on.

 

I know they get dirty over time, but not aware they were failed very often. I cleaned mine a year or so ago. Two 10mm, took about 20 minutes tops.

 

As for the buzzing noise, if you have an Adaptronic ECU. You can select different type of frequency and test it out.

For an OEM, it operates @ 500Hz, but putting it at 250Hz will make a buzzing noise.

SO, if someone who has the ECU and is willing to give it a shot, this might be a good choice.

BTW, I understand many have deleted the ISC valve. But I believe there's a reason why it's there and why OEM factory would put it there. Because THEY actually control IDLE much better given it functioning.

My ISC has been sitting over 4 years covered with dust and debris while I was collecting parts for my rebuild. What I did was sprayed it with some WD40, clean it up and soak it in some ATF over night and brake cleaned it.

Worked like a charm.

-AzEKnightz

 

Just to clarify, I was trying to point out that used ISC valves are inexpensively available because people delete them. They hardly fail, although they do clog up. I'm not saying you should or shouldn't delete them; that depends on the setup.