Editing S130/afmrefresh php (section)

=== Adjusting the Idle Mixture ===

The '''Idle Mixture Adjustment Screw''' is located on the lower side of the AFM near the inlet, as shown below.

https://dev.z31library.com/xenonzcar_archive/s130/images/mixturescrew.jpg

Not all AFMs have this screw. All non-turbo models should, but some turbo models may not. If your AFM does not have the screw, simply skip this step.

The screw meters the amount of air that bypasses the AFM. This only affects the ''air/fuel ratio at idle''.
The principle: while the flapper door signal tells the ECU that only “X” amount of air is entering, the mixture screw allows a small extra amount to bypass — leaning or enriching the mixture depending on screw position.

'''Note:''' The screw is often covered by a plug. On older AFMs, this plug is usually missing. If it’s still there, simply pop it out to access the screw.

===== Adjustment Directions: =====

'''Clockwise'''= richer (less air bypass)'''Counterclockwise'''= leaner (more air bypass)

Turning the screw clockwise closes the air passage, letting less air through, resulting in a richer mixture.
Turning it counterclockwise opens the bypass, letting more air through, creating a leaner mixture.
For best results, use an '''air/fuel ratio gauge''' when making these adjustments.