P1268 - High to Low Side Short in Cylinder #8 Injector Circuit
The P1268 code indicates a short circuit between the high and low sides of the fuel injector circuit for cylinder #8. This typically occurs when the injector coil fails internally, causing a direct short between the two control wires. The engine control module (ECM) detects an abnormal current draw or voltage drop, triggering the code. This can lead to misfires, poor fuel economy, and potential damage to the ECM or injector driver if not addressed.
1. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine misfire on cylinder #8
- Rough idle or hesitation during acceleration
- Decreased fuel economy
- Possible engine stalling
2. Most Common Causes
- Faulty fuel injector on cylinder #8 (internal short)
- Wiring harness damage (chafed or pinched wires) between injector and ECM
- Corroded or loose connector at injector or ECM
- ECM internal failure (rare)
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data. Clear code and test drive to see if it returns.
Step 2: Visually inspect injector #8 connector and wiring for damage, corrosion, or loose pins.
Step 3: Measure resistance across injector #8 terminals (should be 12-16 ohms). A reading near 0 ohms indicates a short.
Step 4: Check for continuity between injector high and low side wires at the ECM connector. If shorted, isolate the harness.
Step 5: Swap injector #8 with another cylinder and see if the code follows. If so, replace injector.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended. Driving with a shorted injector can cause misfires, poor performance, and may damage the ECM or catalytic converter.
How much does it cost to fix?▼
Replacing a single fuel injector typically costs $150-$400 including parts and labor. If wiring repair is needed, costs may vary.
5. Commonly Affected Makes
This is a manufacturer-specific code. The exact manufacturer is not confirmed in our current database.