Air Filter Differential Pressure
Indicates a high differential pressure across the air filter.
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 air filter is getting clogged, causing a blockage that prevents the engine from getting enough air for proper combustion.
What the computer is actually seeing
The Engine Control Module (ECM) monitors the pressure drop across the air filter. Normal conditions will see a pressure differential of around 0.5 to 2.5 inches of water column; anything significantly higher indicates a blockage.
What a healthy reading looks like
0.5 to 2.5 in H2O
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 air filter condition; replace if visibly dirty or clogged. Decision: If replacement fixes the issue, you're done.
- 2Inspect air intake for obstructions or leaks. Decision: If you find a leak or blockage, repair it and monitor if the code returns.
- 3Test the pressure sensor using a gauge. Expected reading should be within normal range. Decision: If the reading is out of spec, replace the sensor.
Common causes
- Clogged air filter
- Intake leaks
- Faulty pressure sensor
- Blocked intake ducts
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, but performance may be affected due to lack of airflow.
Will this code come back after clearing it?
It may return if the underlying issue isn’t resolved.
Why does this code pair with SPN 1382?
SPN 1382 indicates a low-pressure situation, which often coincides with high pressure due to blockage.
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