Exhaust Gas Recirculation (EGR) Temperature Sensor 1 Low
EGR temperature sensor is reading low.
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 EGR temperature sensor measures how hot the exhaust gas is when it goes back into the engine. If it's too low, the computer thinks something's wrong and won't let the engine run efficiently.
What the computer is actually seeing
The engine control module (ECM) expects the EGR temperature to be between 160°F (71°C) and 200°F (93°C) during operation. When the reading drops below 160°F (71°C), it sets the SPN 522 code.
What a healthy reading looks like
EGR temperature should be between 160°F (71°C) and 200°F (93°C).
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.
- 1Check EGR temperature sensor harness for damage or corrosion. Repair as needed. Decision: Is wiring intact? Yes - go to step 2; No - repair wiring.
Common causes
- Faulty EGR temperature sensor
- Wiring issues or connector corrosion
- Faulty EGR valve operation
- Low coolant level affecting EGR operation
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
You can drive, but expect reduced efficiency and possible emissions issues.
Will this code clear itself?
It may clear once the issue is resolved, but often needs a scan tool to reset.
Why does this code pair with SPN 521?
SPN 521 indicates the EGR temperature is high, which often relates to sensor issues.
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