P0134
What This Code Means
No activity detected from the O2 sensor circuit.; Engine misfiring; Rough idle; Internal problem exists inside the engine; Control board malfunction; O2 sensor stuck open/closed; Low fuel level; Low fuel pressure; Fuel in the outer basin tank; Battery voltage below 12.1V for greater than 60 seconds; Completed 26 hour charge cycle, battery voltage below 12.52V, or current draw from charger still greater than 600 mA; Battery voltage above 16.1V; AC input to battery charger missing for greater than five minutes during charging; Controller wrote to the EEPROM more than 500 times in less than four minutes; Air/fuel mix is too rich for more than 10s; Air/fuel mix is too lean for more than 60s; Low Fuel Level; Low Fuel Pressure; No activity detected at O2 sensor circuit; Engine fault code indicating ignition coil issue; No battery voltage at pin 2O on the ECM connector (Wire 172) while pressing manual start; CAN bus resistance on PZ3 connector (pins 1 and 2) is less than 1 ohm or OL (Open/Inf
Possible Causes
- •Faulty O2 sensor
- •Faulty spark plug
- •Vacuum leak
- •Camshaft failed to rotate
- •0 VDC measured at Wire 15H (control board not supplying 12 VDC to hall effect cam sensor during cranking)
- •DTC logged in eeprom
- •Fuel level above 10% but lower than 20% for greater than 60 seconds
- •Low fuel pressure detected for greater than 60 seconds
- •Ruptured tank
- •Low battery
- •Battery Problem
- •Charger Warning
- •Charger Missing AC
- •EEPROM Abuse
- •Gaseous Emissions
- •Ruptured Tank
- •Faulty O2 sensor circuit
- •Faulty ignition coil
- •Faulty Wire 172
- •Faulty ECM
Suggested Actions
- 1Test the O2 sensor.
- 2Replace the O2 sensor if faulty.
- 3Replace spark plugs
- 4Inspect and repair vacuum lines
- 5Replace control board
- 6Warning will clear after engine runs with no DTC codes three times
- 7System detected fuel in the outer basin tank and has triggered the warning
- 8The system detected fuel in the outer basin tank and has triggered the warning.
- 9Repair O2 sensor circuit
- 10Identify correct ignition coil testing procedure for the engine
- 11Test ignition coil
- 12Repair Wire 172
- 13Trace wiring to ECM to determine if ECM is faulty or harness has a short or open
Related Generac Fault Codes
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