P02EF: Cylinder 2 Injector Circuit Range/Performance
What to do
Ask how many cylinders have set this fault. If it is more than one, the problem is very likely the shared wiring or earth rather than several injectors — which is a completely different and much cheaper repair.
Ask for the injector harness to be inspected where it branches to each injector, since that is where these faults concentrate on many engines.
Expect rough running and possibly reduced power.
Do not put off the repair. Unburnt fuel from a cylinder that is not firing correctly can damage the catalytic converter or particulate filter, which costs far more than the original fault.
What this code means
The electrical behaviour of cylinder 2's injector circuit is wrong, without being open or short.
The module judges each injector by the shape of the current waveform it produces when driven, and cylinder 2's no longer matches what a healthy injector gives.
Because injectors on an engine share a harness, the useful question here is how many cylinders are affected — and it separates two quite different faults.
- One cylinder points at that injector or its own connector.
- Several cylinders, especially adjacent ones, point at the shared part of the harness — a common earth, a shared supply feed, or the section of loom where all the injector wires run together under the rocker cover or along the rail.
That shared section is a genuine weak point on many engines. It sits in oil mist and heat, and the branch where individual injector wires leave the main loom is where chafing and terminal fatigue concentrate.
A repair that replaces one injector on a car with three of these codes is treating a harness fault as three part failures. Read all the stored codes before deciding.
Note also that some engines run injectors through a separate injector control module with its own drive stages. Where one is fitted, a failing output there produces this code on the cylinder it drives, with the injector entirely sound.
Likely causes
Start here
- Corroded or loose connector · easy
- Failed fuel injector · specialist
Less common
- Damaged wiring harness · moderate
- Open circuit in injector wiring · moderate
Rare
- Failed injector control module · specialist
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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What makes one worth reading:
- The car — make, model, year and engine. The same fault behaves differently on each.
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