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how to test ford idle pwm valve

Posted: Sun Apr 18, 2010 11:59 am
by ajrenslow
I have my pwm idle valve installed but I cannot get it to move. I have cycled from 0% to 100% with no change. I have installed the new transistor and the diode. 12v to one side of the valve fidle to the other. when I have the setting at 0% pwm then my meter reads 12v beetween the connections, and when it's at 100% it reads 0v, but there is no movement in the valve with either setting. any help would be greatly appreciated.

Re: how to test ford idle pwm valve

Posted: Sun Apr 18, 2010 2:20 pm
by ajrenslow
I think I have it figured out. the valve opens at 0% pwm and closes at 100%. it only opens for about 1 second when I start megasquirt, so I'm assuming that it just stays closed until I start cranking (which I am not ready to do yet). is this right?

Re: how to test ford idle pwm valve

Posted: Thu Apr 22, 2010 11:18 am
by xr2wishy
you must have something wrong, all ford idle valves i've come across are closed till a voltage is applied.
have you got yours set to inverted per chance?
put up your msq and i'll have a peek for you.

Re: how to test ford idle pwm valve

Posted: Thu Apr 22, 2010 10:31 pm
by john.p.clegg
Just try flicking a battery direct across it,be careful there might be an inbuilt diode in it,to see if it does work,then,is your in line diode the right way round?

John :)

Re: how to test ford idle pwm valve

Posted: Sat Apr 24, 2010 9:17 am
by ajrenslow
this is my msq. I haven't done much of anything with it. I tried flicking the battery across the valve and it didn't move but it did make sparks, then reversed polarity and tried it again with same result. however the valve is working because megasquirt moves it, when I turn on megasquirt then the valve moves open for the amount of time that the fuel pump relay comes on. I am assuming that it will then stay closed until I start cranking and then it will open again. I haven't seen any settings to invert the signal except to actually set the pwm% backwards in the idle pwm dutycycle table which is what I have done because that is what seems to be working. where can I find this setting?

Re: how to test ford idle pwm valve

Posted: Mon Apr 26, 2010 4:37 am
by Matt Cramer
Your idle PWM duty table is set to 0% (closed) with the engine cold and 100% (fully open) with the engine warmed up.