Fuel Filter Differential Pressure
Indicates an issue with fuel filter pressure drop.
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 computer monitors the pressure before and after the fuel filter. If the pressure drop is too high, it thinks the filter is clogged and restricts fuel flow to the engine.
What the computer is actually seeing
The engine control module (ECM) monitors the pressure readings from two sensors: one upstream and one downstream of the fuel filter. It calculates the difference; if it exceeds around 5 psi, the code sets.
What a healthy reading looks like
Normal pressure drop should be less than 5 psi at idle and up to 12 psi under load.
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 wiring and connections to the fuel filter and pressure sensors for damage or corrosion.
- 2Inspect the fuel filter for signs of clogging. Replace if necessary.
- 3Measure fuel pressure before and after the filter. Test values should be less than 5 psi difference at idle, under load not exceeding 12 psi difference.
- 4If pressure readings are within spec but the code persists, consider testing or replacing the pressure sensors.
Common causes
- Clogged fuel filter
- Faulty pressure sensors
- Improper fuel flow
- Air in the fuel system
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's not ideal, as it can lead to reduced engine performance and fuel economy. Address it soon.
Will the code come back after clearing?
If the underlying issue isn't fixed, yes, the code will likely return.
Why does this code pair with others?
Related codes often indicate issues in the same system, like fuel delivery or pressure dynamics.
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