P0268 code: Cylinder 3 Injector Circuit High
P0268 means cylinder 3 Injector Circuit High. The code says where to look, not what failed — the fix depends on which cause your car actually has.
What P0268 means
P0268 sets when the ECM detects higher-than-expected voltage on the cylinder 3 injector control circuit. The two broad explanations are a short to battery voltage in the wiring, or excess resistance — a corroded connector, a partially broken wire, or an injector winding that has failed open all raise the circuit's voltage signature. This makes it fundamentally different from a clogged injector, which is a fuel-flow problem the circuit monitor can't see. Only cylinder 3 is flagged, so a resistance comparison or a swap test against a healthy cylinder pins down the failing part quickly. Its companions are P0203 (injector circuit) and P0303 (misfire), both for the same cylinder. And because cylinder numbering conventions vary between manufacturers, double-check where cylinder 3 physically sits on your engine.
P0268 symptoms
- Cylinder 3 misfire or complete dropout
- Rough idle and engine vibration
- Sluggish acceleration and worse fuel economy
- Check-engine light; flashing indicates an active, catalyst-threatening misfire
- Intermittent versions may set the code without drivability complaints
What it costs to fix P0268
Typical range: $60–$450 · about ~0.5–2 hrs of labor
| If the cause is… | Part | Labor |
|---|---|---|
| Fuel injector (single) | $50–$300 | ~0.5–2 hrs |
| Wiring/connector repair | $5–$50 | ~0.5–2 hrs |
A connector cleaning or terminal repair sits at the low end. Injector replacement costs more and varies with access — V-engines that hide injectors under the intake, and direct-injection engines with premium injectors, push toward the high end.
The price swings on which cause it turns out to be — so confirm the cause before paying. Diagnose P0268 for my exact vehicle →
How to fix P0268
Moderate — doable at home with common tools and patience
- Note when P0268 sets
Check the freeze frame and code history. A fault that returns the instant the engine starts points to something solid, such as an open winding or a control wire tied to power; one that only shows after a hot drive or over bumps usually means a cracked connector or a wire breaking inside its insulation.
- Inspect the injector 3 plug for heat damage
Heat soaks into the middle of the engine, and connectors there can turn brittle — check for a cracked shell, a missing seal, or a wire pulled tight against the rail. Gently tug each wire at the back of the connector; one that stretches or moves independently has probably broken inside.
- Use a noid light to see the pulse
On a port-injected engine, clear the codes first (some modules disable a faulted driver), then plug a noid light into the injector 3 harness and crank. No flash with battery voltage confirmed on the feed pin means the control side isn't switching — an open wire, or one shorted to power so both pins sit at the same voltage. A healthy flash puts the injector back under suspicion.
- Check the winding for an open
Measure across injector 3's terminals. OL, or a reading well above its neighbours (healthy high-impedance injectors commonly fall between about 11 and 18 ohms), means the coil is open or failing and the injector needs replacing.
- Repair with solder, not tape
If the fault is in the wire, cut back to clean copper, join with solder and adhesive-lined heat-shrink, and re-secure the harness away from the rail and hot spots. Then clear codes and verify with a drive that includes a full heat soak, since heat is often what opened the circuit in the first place.
DIY or shop? The checks here are approachable: reading freeze frame, inspecting the connector, a noid-light test and an ohm reading can all be done in the driveway, and wire repairs with solder and heat-shrink are a learnable skill. If your engine is direct-injected, skip the noid light and casual probing — those circuits use high-voltage drivers — and follow the service manual or let a shop test it. A shop also makes sense when the open is inside the main loom rather than near cylinder 3.
Tools for the DIY steps: OBD-II scan tool with freeze frame · Noid light set · Digital multimeter · Soldering iron and adhesive-lined heat-shrink · Harness clips or zip ties
Not sure which step applies to your car? Get the likely cause for your exact vehicle before buying anything for P0268.
Start a case with P0268 and your car. Redline weighs these causes against what your car shows, and names the check that would settle it before you buy parts.
Can I drive with P0268?
Redline can’t determine from a symptom or code alone whether your car is safe to drive.
P0268: common questions
What makes a circuit read 'high'?
Two main things: a short that connects the circuit to battery voltage, or added resistance from corrosion, a damaged terminal, or an open injector winding. Both distort the voltage pattern the ECM expects when it fires the cylinder 3 injector, and it sets P0268 in response.
Do I need to replace the injector for P0268?
Not necessarily. Many P0268 cases trace to the connector or harness rather than the injector itself. Test the injector's resistance first — only replace it if it reads open or well out of line with the other cylinders.
The code keeps returning after clearing. Why?
Circuit faults set again as soon as the ECM sees the bad voltage, so clearing without repairing just restarts the clock. If it returns intermittently, suspect a connection that changes with heat and vibration — a corroded pin or a chafed wire that only touches sometimes.
Is driving with P0268 going to damage anything?
The engine itself tolerates a dead cylinder briefly, but the catalytic converter doesn't like the unburned fuel a misfiring cylinder sends its way. Prolonged driving risks an expensive converter failure, so schedule the repair promptly.
Related trouble codes
Don’t have a scanner yet? A ~$25 Bluetooth adapter reads codes like P0268 from your phone. See our guide to the best OBD2 Bluetooth adapters. Run a repair shop? See Redline for shops.
Generic OBD-II reference. Manufacturer-specific behavior varies. Confirm with a scan tool and, for safety-related codes, a professional inspection. Cost ranges are reference ranges, not quotes.
Seeing P0268 on your car?
Every problem becomes a Case. Tell Redline what the car is doing: it shows what the evidence supports, what’s still missing, and what to check next, before you approve a repair.
“Inner pad ~1 mm. Outer pad 3 mm.”
Next: check the slide pins move freely before buying parts.