Turbine Outlet Temperature
Indicates abnormal turbine outlet temperature in the engine system.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The turbine outlet temperature is higher than normal, which could mean the turbocharger is overheating or there is an issue causing inefficient airflow or excessive heat.
What the computer is actually seeing
The engine control module (ECM) monitors the turbine outlet temperature sensor, which should read around 300-500°F during normal operation. If it exceeds 600°F, the ECM triggers a fault.
What a healthy reading looks like
Turbine outlet temperature should be between 300°F and 500°F; over 600°F triggers a fault.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Inspect wiring and connectors to the turbine outlet temperature sensor for damage or corrosion. Check for tight connections.
- 22. Verify the actual temperature reading at the sensor with a scan tool. Compare it to the expected range (300°F to 500°F). Decision: If reading is above 600°F, proceed to step 3; if normal, consider replacing the sensor.
- 33. Check the turbocharger for signs of wear or damage. Inspect for oil leaks or abnormal noises. Decision: If turbo is faulty, replace it; if not, continue to step 4.
- 44. Inspect the cooling system for proper operation. Check coolant levels and flow. Decision: If coolant is low or flow is restricted, address the cooling issue; if all is good, consider replacing the temperature sensor.
Common causes
- Faulty temperature sensor
- Wiring issues (shorts, opens, or corroded connectors)
- Turbocharger malfunction
- Insufficient coolant flow
- Exhaust system restrictions
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code active?
While you may still drive, overheating can lead to serious turbo or engine damage. It's better to address the issue soon.
Will the code come back after I clear it?
If the underlying issue isn't fixed, the code will likely return. Make sure to diagnose thoroughly.
Why does this code show up with SPN 146?
SPN 146 and SPN 147 often occur together because they both relate to turbo temperature issues.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
Start guided diagnostic →