At idle, the voltage from the mass air sensor, i.e the potentiometer should be around 0.7V. There are 3 terminals on it, one is ground, one is 12V and the third one should be at 0.7V (w.r.t. ground). Check this voltage, and if it not 0.7V, adjust it, there is a little screw on the sensor.

Also when on idle, make sure that the air sensor's plate is at the top.

Saumil

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Saumil S. Patel