myztik, does you car idle at a steady 600rpm +-50rpm ?

If it does not and hunts up and down at idle try this:

Turn the car off and then dis-connect your Air Flow Meter Plug from the black plastic intake pipe. This is just before the Accordian pipe bend that leads into the intake pipe to the turbo.

Start the car again (Check engine light will be on). Now if you get a rock steady 600 RPM idle its a dirty Air Flow Meter problem. The AFM can be cleaned with CRC Contact cleaner.

The AFM's on 99/00 WRX's do not like getting dirty and especially hate oiled filters.

J

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