P0090: Fuel Pressure Regulator A Control Circuit/Open
Do not keep driving
Expect starting difficulty or a marked loss of power. Have it diagnosed before further driving.
What this code means
An electrical fault in the circuit controlling the fuel pressure regulator. With the circuit broken the regulator defaults to a fail-safe state, which on most systems means either minimum or maximum pressure rather than anything useful — hence a fault that presents as a hard start or a severe limp rather than a subtle performance loss.
Likely causes
Start here
- Open circuit in regulator control wiring · moderate
- Failed fuel volume regulator · moderate
- Corroded or loose connector · easy
Less common
Rare
- Control module driver failure · specialist
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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