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Dan, Technician
Category: Kia
Satisfied Customers: 24416
Experience:  Independent Shop Experience, 2 Year Automotive Diploma, & Access to Information Database
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2002 kia rio: 60,000 miles..water pump..ran great..25 miles it idles

Resolved Question:

2002 kia rio 60,000 miles just replaced timming belt water pump pcv valve plugs and wires ran great vfor 25 miles it idles ruff and p1166 code it triping the check ngine light. what is the code mean and what the most likely fix
Submitted: 6 years ago.
Category: Kia
Expert:  Dan replied 6 years ago.

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I'd start by replacing oxygen sensor, its a hard code to diagnose without a high end scantool....If that doesnt help you will need to check for vacuum leaks and fuel pressure.



P1166 Oxygen Sensor System Lambda Bank Controller At Limit (Bank 1)

Possible CausesSetting Conditions
  • Base engine "mechanical" fault affecting one or more cylinders
  • Check for air leaks after the MAF sensor mounting location
  • Check for air leaks in the exhaust manifold and in the exhaust pipes
  • Check for air leaks in the Air Induction system (e.g., in the intake manifold)
  • Fuel control sensor is out of calibration (i.e., ECT, IAT or MAP)
  • Fuel delivery system supplying too little fuel during cruise or idle periods (e.g., faulty fuel pump or dirty, restricted fuel filter)
  • Fuel injector (one or more) dirty or pressure regulator has failed
  • HO2S has failed (it may be contaminated with fuel, silicone or water)
  • Vehicle driven low on fuel or until it ran out of fuel
Engine running; system voltage from 10-16v, ECT signal more than 158ºF, Lambda control active, and the PCM detected that the Lambda control was out of limit. The Lambda Closed Loop control system is included in the Engine Control system in order to regulate the Lambda upstream with the HO2S signal. Rich air/fuel mixtures generate the high concentrations of CO, H2, and HC while lean air/fuel mixtures generate high concentrations of NOx, and free Oxygen.

This code sets in 2 Trip(s).
This code will turn on the MIL (Malfunction Indicator Lamp)

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