Exhaust Pressure Sensor Signal Too High
Exhaust pressure sensor is reporting a signal that is too high for normal operation.
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 exhaust pressure sensor measures how much pressure is in the exhaust system. If it's reading too high, it might mean there's a blockage or a problem with the exhaust flow.
What the computer is actually seeing
The engine control module (ECM) is monitoring the exhaust pressure through the sensor and expects to see voltages between 0.5 to 4.5 volts. If the signal exceeds 4.5 volts, it triggers this fault code.
What a healthy reading looks like
Normal exhaust pressure values should reflect voltages between 0.5V (low pressure) to 4.5V (high pressure). Excessive voltage reading (above 4.5V) requires further investigation.
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. Check the wiring and connectors leading to the exhaust pressure sensor for any damage or corrosion. Secure connections if necessary.
- 22. Inspect the exhaust system for any visible blockages or damage that could restrict flow.
- 33. Using a multimeter, test the voltage at the exhaust pressure sensor connector with the engine running. Compare readings to expected values (0.5V to 4.5V).
- 44. If voltage is above 4.5V, replace the exhaust pressure sensor.
- 55. If replacing the sensor doesn't resolve the issue, check for exhaust flow obstructions (like a clogged DPF).
- 66. Clear the fault codes and perform a road test to see if the code reappears.
Common causes
- Clogged DPF (Diesel Particulate Filter)
- Faulty exhaust pressure sensor
- Blocked exhaust system (like a foreign object in the pipe)
- Leaking exhaust pipes or connections
Typical repair cost
$$-$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's not recommended to drive the vehicle as excessive exhaust pressure can lead to more serious damage, including turbo failure.
Will this code come back after clearing it?
If the underlying issue isn't fixed, yes, it will likely return.
Why does this code often pair with SPN 1347?
SPN 1346 and SPN 1347 both relate to the exhaust pressure sensor and conditions affecting exhaust flow, often occurring together.
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 →