Function of sensor plate?

[nixter]

I guys, I need some help understanding the funtion of the sensor plate and how it relates to the fuel system. I'm talking about the sensor plate under the air filter. Also could someone tell me the proper action for the plate with car on/off? It's related to some starting issues I've been having. Sometimes it's firm to push up and then drops easily. Other times it's firm to push up once, drops easily and then moves up and down freely after that.

Thanks,

Nik.

[Jared at Pelican Parts]

The vacuum created from the engine running causes the sensor plate to rise in it's bore. The sensor plate is connected mechanically to a control plunger which allows fuel to be distributed to each cylinder. So, the more vacuum created (i.e. pushing the pedal down) the more the plate rises, and more fuel is distributed via the control plunger..

there shouldnt be a great deal of resistance in the action of the plate..

The plate itself might be misaligned in relation to the bore. If this happens, it can drag a bit. However it's tricky to get the plate perfectly centered.

The other thing it can be is that the control plunger may be binding. This is usually caused by dirt or gummed fuel getting in there and preventing it from moving freely. I've heard that it is possible to remove the fuel distributor (on the top and back of the airbox with the lines coming out of it) and use compressed air to blow the piston out, then carefully clean the piston and the bore...