Cold idle air valve

[Lesliehedley]

I have an Emerald ECU fitted to my car and tuned by Joolz. At the time Joolz set up the ECU I had no idle air valve fitted. I am now attempting to fit an idle air valve to be controlled by the Emerald. I have removed the extra air valve that was fitted to the flapper system and made a bracket to fit the two wire air valve in it's place. My plan is to use the old pipework for the extra air valve to take the air from the throttle plate area and feed it through the valve to the plenum where the extra air valve used to feed it, if I understand how the original system worked. Here are two pictures of the installation so far. Can anyone confirm that I've understood how the system works and is there an easier way to fit a two wire valve than the one I've tried. The pipe work is a bit convoluted from the valve to the plenum. TIA.

[Lesliehedley]

Hi Martin, could you tell me what PWM value and update rate you are using for your valve. Emerald suggest 300Hz and 10 msecs but that's for any 2 wire valve. I'm wondering if this is the wrong value for this type of valve as I am having difficulty getting the valve to work properly. I find that if I open the valve to a value, for instance 50 from a value of 30 it opens the valve a different amount compared to moving the valve to 50 from a value of 70. I thought possibly the valve was sticking but I have a new valve and a used valve and they both exhibit the same behaviour. I'm wondering if a different PMW value and update rate might help.

[Lesliehedley]

Hi Martin,
Thanks for the reply. I have got the valve working correctly by changing the frequency to 100Hz. But I still have a problem. With the valve fully closed (at 34% on my valve) there is so much air leaking past the valve that even with the idle speed screw on the plenum fully shut I can't get the idle down to where it should be when the engine is hot. I am using a Bosch valve at the moment so I think I need to try a different type of valve.