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Microsquirt: idle valve confusion

Posted: Thu Dec 27, 2007 12:28 pm
by 65looter
I've been through the :RTFM:
No stepper IAC control: In order to make room for the dual ignition inputs and dual outputs, the ability to to control a stepper IAC was removed. PWM Idle valves, as well as on/off idle valves, can still be used.
I'm getting the "'DarkStar' Custom IAC Body for Jeep Stepper Motor Idle Air Controllers"
http://www.diyautotune.com/catalog/cust ... -p-69.html

Does that mean it will not work if I use the "IAC valve from a Jeep 4.0l motor" (from DIYautotune description)?


Thanks

Re: Microsquirt: idle valve confusion

Posted: Thu Dec 27, 2007 1:31 pm
by MegaScott
65looter wrote:I've been through the :RTFM:
No stepper IAC control: In order to make room for the dual ignition inputs and dual outputs, the ability to to control a stepper IAC was removed. PWM Idle valves, as well as on/off idle valves, can still be used.
I'm getting the "'DarkStar' Custom IAC Body for Jeep Stepper Motor Idle Air Controllers"
http://www.diyautotune.com/catalog/cust ... -p-69.html

Does that mean it will not work if I use the "IAC valve from a Jeep 4.0l motor" (from DIYautotune description)?


Thanks
Yep..That's exactly what it means.

I would use a PWM idle valve..such as the Bosch or a converted Ford Valve. I guess I'll have to convert one of the Ford valves for my Cougar and take pics......

Posted: Tue Jan 01, 2008 7:38 am
by 65looter

Posted: Tue Jan 01, 2008 11:02 am
by MegaScott
no, thats a stepper motor.

You need something like this -
Image

You tap the two holes and put in pipe nipples, then one hose goes to the manifold, the other to the air filter. Also i've seen people make a plate and bolt it to the bottom, then drill and tap holes in the plate.

or this -

Image

The two wire bosch valve as called out in the MegaManual.

The key here is that you want a Fidle valve with two wires.....not three or four wires.

Scott

Posted: Tue Jan 01, 2008 11:19 am
by 65looter
Thanks Scott.

Posted: Tue Jan 01, 2008 11:56 am
by 65looter
ok, I just go myself a new Ford idle valve 2 wires
Image

Posted: Tue Jan 01, 2008 12:19 pm
by MegaScott
That should work...

You might have to try either hole to the Manifold vacuum, there's two kinds of valves Ford uses, and it depends on which year you bought to determine which way the air flows through the valve. Early valves are closed with no input, late model valves are full open with no input, of course with engine vacuum applied, and by input I mean electrical input.

Edit - Some of the solenoids have a back EMF diode in them, so it may only work with the input electrical polarity one direction.

Posted: Tue Jan 01, 2008 12:23 pm
by 65looter
MegaScott wrote:That should work...

You might have to try either hole to the Manifold vacuum, there's two kinds of valves Ford uses, and it depends on which year you bought to determine which way the air flows through the valve. Early valves are closed with no input, late model valves are full open with no input, of course with engine vacuum applied, and by input I mean electrical input.
It's the item 230206542735 on eBay.
(If it's against the rules to post an eBay link, please delete)

Posted: Tue Jan 01, 2008 12:33 pm
by MegaScott
That's the late model valve...Should be fast idle with no electrical input, then with progressively increasing duty cycle the idle speed should go down.


Also since it's for the smaller engine, it should have smaller holes which are easier to tap out for nipples. dunno, for you probably some size of British pipe thread? Here, 3/8"NPT works on most of the valves I've seen. Thus the reason some guys make a plate, you can use whichever size you want, as long as enough air can flow through to give you a fast enough idle.

Re:

Posted: Wed May 14, 2008 4:07 am
by 65looter
65looter wrote:ok, I just go myself a new Ford idle valve 2 wires
Image

Just to make sure I got that right.
This valve in the picture above is a Fast Idle valve, isn't it?

I'm in Megatune and also with the help of the manual at http://www.megamanual.com/mt28.htm#sd
What would Algorithm be set to: Solenoid? is that right?