P1166 Honda Code - Air/Fuel Ratio Sensor 1 Heater Circuit Malfunction
Quick Answer
The Air/Fuel Ratio (A/F) sensor 1 is installed in the exhaust system and detects oxygen content in the exhaust gas. Common causes include Faulty Air/Fuel Ratio Sensor 1, Air/Fuel Ratio Sensor 1 harness is open or shorted, Air/Fuel Ratio Sensor 1 circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1166 Honda indicates Air/Fuel Ratio Sensor 1 Heater Circuit Malfunction.
- Common causes
- Common causes include Faulty Air/Fuel Ratio Sensor 1, Air/Fuel Ratio Sensor 1 harness is open or shorted, Air/Fuel Ratio Sensor 1 circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P1166 Honda Description
If the A/F sensor (sensor 1) voltage is low, the air/fuel ratio is lean, and the ECM uses A/F feedback control to issue a Rich command. If the A/F sensor (sensor 1) voltage is high, the air/fuel ratio is rich, and the ECM uses A/F feedback control to issue a Lean command.
What are the Possible Causes of the DTC P1166 Honda?
- Faulty Air/Fuel Ratio Sensor 1
- Air/Fuel Ratio Sensor 1 harness is open or shorted
- Air/Fuel Ratio Sensor 1 circuit poor electrical connection
How to Fix the DTC P1166 Honda?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P1166 Honda code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P1166 Honda code?
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Need Help with the Code?
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Information for Specific Honda Models
- P1166 1996 Honda Civic — Air/Fuel Ratio Sensor 1 Heater Circuit Malfunction
- P1166 1997 Honda Civic — Air/Fuel Ratio Sensor 1 Heater Circuit Malfunction
- P1166 1998 Honda Civic — Air/Fuel Ratio Sensor 1 Heater Circuit Malfunction
- P1166 1999 Honda Civic — Air/Fuel Ratio Sensor 1 Heater Circuit Malfunction
- P1166 2000 Honda Civic — Air/Fuel Ratio Sensor 1 Heater Circuit Malfunction
Frequently Asked Questions about P1166 Honda Code
No Frequently Asked Questions about P1166 Honda Code found.
Discuss the causes and fixes for P1166 Honda OBDII Code
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to change the sensor with a new one, the error code of the computer and the board is removed?
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My vehicle idle is too high,and I have done so many things, still yet no results.
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Besides the high idle, are there any more symptoms? what engine codes? what model and year is your Honda?
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Just replaced upstream (A/F) oxygen sensor after getting code 1166 and the code will not go away.
If there is a bigger scam than the Pennsylvania Emissions, I hope I never see it. -
1998 honda accord 2.3l has codes p1166 and p1167 I replaced both o2 sensors and the codes didn't go away so checked the fuses I found the one on the drivers side fuse box and it was good but when I tried to check the laf fuse on the passenger side fuse box it was empty and theres no wires
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