P0093: the fuel system has detected a large leak
The engine control unit can tell when the fuel system is losing more fuel than it's delivering to the engine, by comparing how much fuel it's commanding against the fuel pressure it actually sees. This code means it's detected a leak large enough to affect how the engine runs, not a slow drip it can quietly correct for. It doesn't say where in the fuel system the leak is, only that there is one.
You might notice
- The engine warning light comes on
- You may notice a smell of fuel, or the engine may run poorly or refuse to start
What this code means for driving
Stop driving
The high-pressure fuel system has logged a pressure fault or a leak.
Stop driving now — leave it where it is until a garage has checked it. If you smell fuel or you see fuel under the car, that's an emergency: pull over immediately.
On a car with a combustion engine: A leak on a high-pressure fuel system is a fire risk. Do not investigate it yourself.
This is what P0093 means taken alone, and that part won't change no matter what else your scan turns up. What's actually causing it can still depend on the rest of your codes. Read it with your other codes.
What the code itself says
P0093 is a powertrain (engine, gearbox and drive system) code, and the 0 after the letter means it is a generic code with a standard meaning.
Grouped here as: Engine running, fuelling and misfires — Air metering, fuelling, ignition, misfire, idle, boost, knock, oxygen sensors and the catalyst, all working together in the running engine. That grouping is ours, to help explain the code. The code's official family is the letter at the start.
This page is generic. Your car isn't.
A code on its own only tells you what the sensor saw, not what's actually wrong — and that changes next to your other codes. Read this one together with the rest of your scan and we'll work out what's really going on.
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