Idle Surge

[artpogi]

Engine temperature is normal, with the A/C off, the idle suddenly surge from 800 to 1000 and will hold at 1000 for about 10 to 20 seconds then back to 800 again.

Has anybody experienced this? Medyo nakaka-ilang kasi, parang nagre-rev mag isa yung kotse.

Air filter is regularly cleaned, plugs are okay (recently checked this)

car is Lancer 97 GLXi.

is this normal? or is this a sign of the servo nearing its end? Ano pa ba ang pwedeng cause nito?

Thanks.

[Ungas]

I have read from another thread that a faulty Sanden Servo Kit causes erratic idling. I could be wrong, but that's what the guys posted.