Emission Control System Performance - Incorrect Operation
The emission control system is not functioning properly, affecting emissions performance.
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 truck's computer is noticing something wrong with the way the emissions system is working. It might be due to a faulty sensor or a clog somewhere in the system.
What the computer is actually seeing
The engine control module (ECM) detects that the readings from the emission control system sensors are out of expected ranges, indicating that the system is struggling to manage emissions as it should.
What a healthy reading looks like
Normal operation should show exhaust gas recirculation (EGR) temperature between 150-300°F, EGR flow rate between 10-30%, and pressure readings near 0 PSI when idle.
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 vehicle’s EGR connections and wiring for any visible damage or corrosion. Decision point: Repair or replace faulty wiring/connectors if found.
- 22. Measure EGR valve operation by applying direct power and ground; it should move freely. Decision point: Replace the EGR valve if it doesn't operate correctly.
- 33. Inspect EGR passages for blockages or carbon buildup. Use a flexible brush if needed. Decision point: Clean passages if clogged, replace EGR if not fixable.
- 44. Test the EGR temperature sensor for proper response, looking for voltage changes with changes in temperature. Decision point: Replace the sensor if readings are out of range.
Common causes
- Faulty EGR valve or sensor
- Blocked EGR passages
- Wiring harness issues to EGR components
- Faulty exhaust temperature sensors
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It’s moderate severity; you can drive, but fix it soon to avoid emissions problems.
Will this code come back after clearing it?
If the underlying issue isn't fixed, yes, the code will likely return.
Why does this code appear with SPN 5560?
SPN 5560 relates to EGR malfunction; both codes indicate emissions control system issues.
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