Some Sportage information here

[hvac1000]

1997 – 2000 SPORTAGE P0101/HIGH IDLE (Runs Like Shit) PROBLEM
(The dealer found this in the KIA Maintenance Manuals after calling the manufacturer.
I asked the mechanic for a copy before the manager came in and he gave it to me. The
manager found out and demanded I return it. I told him I would return it if he would
return the $840.00 they charged me for the repair…He said “No” and I left.)

1. Remove all terminals from connectors C144 (TP Sensor) / C129 (MAF Sensor), solder terminals, re-tension then reinstall back into the connectors. Make sure the MALE terminal pins on the Sensor side are not twisted and are in alignment before reconnecting.
2. Disconnect C123 / C124 / C161, remove secondary lock (if necessary) and re-tension all terminals. NOTE: Always add one droplet of “Stabilant 22A” after tensioning the terminals, then apply to ECT, IAC, and IAT sensors.
3. Improve grounds at: G103 (RF Kick Panel Area), G104 (at Intake Manifold), G105 (Battery Tray Ground).
4. Solder Slices: S113 (around Transmission Bellhousing), S114 (at rear of Fuel Injection Harness, near #4 Fuel Injector), S116 (at front of Fuel Injection Harness, near #1 Fuel Injector), S192 (near Bulkhead Grommet at ECM (pin 71), S193 (approx 4 – 8 inches from Bulkhead Grommet), S194 (at G103 Branch), S195 (at MAF Sensor near DLC Split). Splices may vary depending on Model / Year of vehicle.
5. Make sure the air filter is clean (especially in dusty / desert areas).
6. Start the engine and monitor the TP and MAF values. The MAF Sensor should read approximately 3.5 to 3.6 gms/sec. The TP value should be 400 to 600 mv, or 10 to 11 degrees at idle.
7. Road test the vehicle and ensure all the readiness tests have passed and been completed. During the road test, check the HO2S1 as the vehicle is under hard acceleration, the voltage should be high (noting a “Rich” condition). If the value stays low (indicating a “Lean” condition) the fuel system should be checked for contamination of blockage. Also make sure the Catalytic Converter is not cracked and inducing false reading at the O2 Sensor.

Note: The dealer WILL try to avoid soldering the S113 splice at the transmission bellhousing as it is a major “Pain In The Ass”. Make sure this splice is repaired

[LMP]

Thanks for the "official" version. Corrosion or poor contact on ALL sensors or actuators is an often reported factor for a lot of engine idiosyncrasies....Too bad the little truck is plagued with such "back to the basics" problems...that end up costing an arm and a leg. One always expects that an electrical connecttion does conduct electricity....something that is not so obvious after all.