Engine idle speed

2000 MAZDA PROTEGE
180,000 MILES • 1.6L • 4 CYL • 2WD • MANUAL
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ZEMORZEMOR
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The idle speed is at 850 with all accessories off. in the sticker underneath the hood it says it should be 700 . what are the causes ? I checked for vacuum leak, none.

Thank you
Apr 24, 2018 at 11:53 PM
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MHPAUTOS
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May be a faulty idle control motor. Also, if the A/C is on the base idle will be elevated as well.
Apr 25, 2018 at 12:12 AM
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ZEMORZEMOR
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when the car was idling i unplug the IAC connector, no change at the rpm. so i guess the IAC is closed. the TPS was reading zero percent. my questions are, what the TPS should read at idle? the throttle body has two screws one on the spring loaded lever where the accelerator cable hooked too. and another one screw in the throttle body i think it restrict the air going in . because that screw it like plug a bypass if i screw it in and allow air goes more when i do not. so do i need to adjust those screws?
Apr 26, 2018 at 1:41 PM
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ZEMORZEMOR
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okay, the first screw is called throttle body plate stop screw . the second is called idle adjustment screw. forgot to tell you the idle went up after i cleaned the throttle body and for your information. i do not have AC.
Apr 26, 2018 at 2:16 PM
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