Exhaust Pressure Sensor Out of Range (Low)
The exhaust pressure sensor is reading lower than expected.
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 detects the pressure in the exhaust system. If it's too low, it could mean there's a leak or a blockage somewhere.
What the computer is actually seeing
The ECM expects the exhaust pressure to be within a certain range. If it measures significantly lower than this range (for diesel systems, usually below 5 psi while the engine is running), it triggers this fault code.
What a healthy reading looks like
Normal exhaust pressure readings are typically between 5-15 psi under load and idling should not drop below 3 psi.
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 the wiring and connector to the exhaust pressure sensor for any signs of damage or corrosion. Repair or replace as necessary.
- 22. Check for exhaust leaks upstream of the exhaust pressure sensor. Any leaks should be repaired to restore proper pressure readings.
- 33. With a scan tool, live monitor the exhaust pressure readings. If they are still below 3 psi while running, continue to step 4.
- 44. Swap and test with a known good exhaust pressure sensor. If readings return to normal, replace the faulty sensor.
- 55. If the problem persists, inspect the DPF for restrictions or clogs, as this can cause low pressure readings.
Common causes
- Faulty exhaust pressure sensor
- Wiring issues or bad connectors to the sensor
- Exhaust leak before the sensor
- Clogged DPF (Diesel Particulate Filter) or exhaust components
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code active?
It's not recommended to drive long distances as it can lead to reduced engine performance and potential damage.
Will this code come back if I clear it?
Yes, if the issue causing the low pressure is not resolved, the code will likely return.
Why does this code sometimes pair with SPN 1103?
SPN 1103 indicates exhaust back pressure sensor, which works closely with SPN 1137. An issue in one can directly affect the other.
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 →