Cause
Faulty fuel temperature sensor
Fuel density changes with temperature, so the module uses this to convert a commanded volume into the right injector opening time. A wrong reading gives a consistently wrong mixture with nothing mechanically amiss — poor economy and emissions failures rather than a driveability complaint.
Typically a moderate job.
Codes this can cause (16)
Codes where this is a likely explanation first, rather than merely a possible one.
- P0168 Fuel Temperature Too High Likely for this code Moderate
- P0180 Fuel Temperature Sensor A Circuit Likely for this code Moderate
- P0181 Fuel Temperature Sensor A Circuit Range/Performance Likely for this code Moderate
- P0182 Fuel Temperature Sensor A Circuit Low Likely for this code Moderate
- P0183 Fuel Temperature Sensor A Circuit High Likely for this code Moderate
- P0185 Fuel Temperature Sensor B Circuit Likely for this code Moderate
- P0186 Fuel Temperature Sensor B Circuit Range/Performance Likely for this code Moderate
- P0187 Fuel Temperature Sensor B Circuit Low Likely for this code Moderate
- P0188 Fuel Temperature Sensor B Circuit High Likely for this code Moderate
- P2A4B Alternative Fuel Temperature Sensor Circuit Likely for this code High
- P2A4C Alternative Fuel Temperature Sensor Range/Performance Likely for this code High
- P2A4D Alternative Fuel Temperature Sensor Circuit Low Likely for this code High
- P2A4E Alternative Fuel Temperature Sensor Circuit High Likely for this code High
- P2A4F Alternative Fuel Temperature Sensor Circuit Intermittent/Erratic Likely for this code High
- P0184 Fuel Temperature Sensor A Circuit Intermittent Moderate
- P0189 Fuel Temperature Sensor B Circuit Intermittent Moderate
Information, not instruction
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