P2357: Cylinder 10 Pressure Too Low
What to do
Ask for the fuel-on versus fuel-off pressure comparison before any mechanical work is quoted — it is the free split between an injector (moderate) and internal engine work (not). The named cylinder is real information; do not let a diagnosis wander to whole-engine guesses.
What this code means
Cylinder 10's measured pressure is genuinely low — not a circuit fault, but the cylinder itself producing less than its siblings.
This is a compression test the engine runs on itself, every drive. The manual version — plugs or injectors out, gauge in, cranking — is exactly what this sensor renders unnecessary: the module already knows each cylinder's pressure and has flagged the weak one by name. Low pressure with fuel off (overrun, cranking) is mechanical — a burnt or sticking valve, worn rings, a leaking pressure path — while low pressure only when firing points at delivery: an injector under-fuelling the cylinder. That fuel-on/fuel-off split is the diagnosis, and the scan data carries it.
The sensor lying low is possible but convicted quickly: the P2349 overrun comparison shows whether this cylinder's compression trace matches its siblings, which a lying sensor fails and a genuinely weak cylinder passes differently.
Likely causes
Start here
- Low engine compression · specialist
- Failed fuel injector · moderate
Less common
- Burnt or leaking valve · specialist
- Faulty cylinder pressure sensor · moderate
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
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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