reductant injector 'B' performance problem
There's an issue with the performance of the second DEF injector.
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 second diesel exhaust fluid (DEF) injector isn't spraying properly, which can cause increased emissions and reduced engine performance due to improper urea solution delivery.
What the computer is actually seeing
The engine control module (ECM) monitors the DEF injector using feedback from the exhaust aftertreatment system. It expects a specific flow pattern. If it detects an abnormal performance level, such as no flow when it should, or flow rates outside of the expected range, it triggers this code.
What a healthy reading looks like
The DEF injector should provide a consistent spraying pattern; flow rates should be between 0.1 to 1.5 L/hr during active regeneration.
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 DEF level in the tank; it should be above the minimum threshold (usually above 1/4 tank).
- 2Inspect wiring and connectors to injector 'B' for damage or corrosion; repair as necessary.
- 3Test the DEF injector 'B' for proper operation; confirm spraying function and flow rate.
- 4Use a scan tool to monitor the DEF flow rates during sensor testing; values should align with expected flow rates. If out of range, replace the DEF injector.
Common causes
- Clogged DEF injector 'B'
- Wiring harness issue or connector fault
- Faulty ECM
- Low DEF level or contaminated DEF
- DEF quality problem (too much water or impurities)
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's not recommended to drive far as it can lead to increased emissions and potential engine performance issues.
Will this code return after repairs?
If the repair is done correctly and the DEF system is functioning properly, it should not return.
Why does this code sometimes come with P2044?
Both codes relate to the DEF injection system; P2044 indicates an issue with injector 'A', making them common together.
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