Exhaust Gas Temperature Sensor Circuit Low (Bank 1 Sensor 1)
Common Symptoms
- Check engine light illuminated
- Reduced engine power or limp mode activation
- Turbocharger boost control issues
- Poor acceleration or turbo lag
- Black smoke from exhaust under load
- Increased fuel consumption
Most Likely Root Causes
- Faulty exhaust gas temperature sensor
- Damaged or corroded wiring harness to EGT sensor
- Sensor connector corrosion or moisture intrusion
- Exhaust manifold or turbo heat damage to sensor wiring
- Poor sensor ground connection
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Component Location
The exhaust gas temperature sensor is typically located in the exhaust manifold or turbocharger inlet housing on bank 1 upstream position.
Manufacturer Notes
Diesel engines with emissions systems and turbocharged gasoline engines commonly use multiple EGT sensors for active regeneration and boost control monitoring.
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