P1166 2002 HYUNDAI SANTA FE Possible Causes
- Air leak or restriction in the intake or exhaust system
- Dirty engine oil or oil level too high
- Pre-HO2S or MAFS contamination
- Fuel system
- EVAP system
- Faulty sensor signals
How to Fix Code P1166 2002 HYUNDAI SANTA FE?
Start by checking the “possible causes” listed above. Visually inspect the corresponding wiring harness and connectors. Look for damaged components and check for broken, bent, pushed out, or corroded connector pins.
Possible Symptoms
- Engine light on (or engine service warning light soon)
P1166 2002 HYUNDAI SANTA FE Meaning
The Lambda closed-loop control system is included in the engine control system. The control system regulates the upstream lambda with the HO2S signal. Rich mixtures generate high concentrations of CO, H2, and HC. Lean mixtures generate high concentrations of NOx and free oxygen.
If the lambda controller reaches the maximum or minimum threshold, feedback control is no longer possible and emissions will be increased. The ECM sets DTC P1166 if no proportional fuel adaptation occurs for a defined time after the lambda controller reaches its minimum or maximum threshold.