2003 Hyundai Tiburon High Idle

2003 Hyundai Tuburon 4cyl.
Started the car and the idle went up to 4000 rpm and will not go down. Any advice on where to start would be greatly appreciated.

Thanks,

Eric Any previous work or maintenance been done recently?

Is the throttle plate closed or is the throttle cam sitting on the stop?

Have you checked for vacuum leaks?

If the throttle plate is fully closed and there are no cables binding or vacuum leaks, tap on the idle speed actuator with the handle of the screw driver to see if the idle comes down. If it does, replace the actuator. If it doesn't let us know and we will give you more information. discretesignals wrote:Any previous work or maintenance been done recently?

-changed plugs and wires 2 months ago

Is the throttle plate closed or is the throttle cam sitting on the stop?

-Closed

Have you checked for vacuum leaks?

-No

If the throttle plate is fully closed and there are no cables binding or vacuum leaks, tap on the idle speed actuator with the handle of the screw driver to see if the idle comes down. If it does, replace the actuator. If it doesn't let us know and we will give you more information.


-No change when tapping with Screwdriver

Errror Codes:

P0121 – TPS/Pedal Position Sensor A CKT Range/Perf
P0123 – TPS/Pedal Position Sensor A Circuit High Input
Car idle would go up to @3500 to 4000 RPM at Start up and not go down. Reset codes with Computer and now the RPM surge up and down between 1500 to 2500 RPM.

Thanks,
Eric Do you have a Digital Voltmeter? Sounds like a TPS problem, Let us know and i or someone can explain how to check your tps. Bj_one wrote:Do you have a Digital Voltmeter? Sounds like a TPS problem, Let us know and i or someone can explain how to check your tps.


Yes, I have one. There are three wires coming off the throttle position sensor connector. Inspect the wires coming off the connector and make sure they aren't chaffing on something or broken. Unplug the connector and inspect the terminals inside the connector. Make sure they aren't contaminated or damaged.

With the connector unplugged, the blue/red wire should have 5 volts on it with the ignition on. The white wire should have 5 volts with the ignition on also. The last wire, orange, you need to check continuity to ground with an ohm meter. It should have close to 0 ohms. If that is good, reconnect the connector onto the sensor.

Next, take a paper clip and back probe the white wire and connect your red lead to the paper clip. Then connect your black lead to the battery ground and watch the voltage on the meter's display with the ignition on. With the throttle closed the voltage should be around .6 volts. The voltage should increase in a linear fashion as you open the throttle. At wide open throttle the voltage should be around 4.5 volts. If you see no voltage change, you see dead spots as you open the throttle, or your voltages are above 4.5 volts or below .5 volts, you probably have a faulty throttle position sensor.
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