P2B06: Cylinder 7 Injection Pulse Performance

What it means

The ECM detects that the injection pulse on cylinder 7 does not produce the expected combustion result. Pulse width, timing, or quantity drift compared to the bank average.

At a glance

• Usually lights the check-engine light
• Affects emissions; the car can fail an emissions test

How it works

The ECM evaluates the combustion response to cylinder 7's injector command and compares that response with the other cylinders on its bank. This code is stored when cylinder 7's injection pulse performance departs from the expected pattern, which may reflect injector wear or fuel that is not burning as expected.

Common causes

Most likely first.

1. Injector aged - flow characteristic drifted
2. Fuel quality affecting injection result

Symptoms

• Check-engine light may be on
• Rough idle or engine vibration
• Hesitation or reduced power

How to diagnose it

1. Read freeze-frame and cylinder-specific misfire or fuel-balance data to determine whether cylinder 7 is the one deviating.
2. Review fuel level and recent refuelling, particularly if symptoms appeared after using a different fuel source.
3. Inspect cylinder 7's injector plug and wiring for corrosion, looseness, rubbing, or heat damage.
4. Compare cylinder 7 injector command and contribution readings with the other cylinders using live scan data.
5. If cylinder 7 remains the outlier, have injector flow and spray checked against the manufacturer's specification.

Common fixes

• Use the vehicle's specified fuel and reassess if poor fuel quality is suspected.
• Repair damaged wiring or a poor connection at the cylinder 7 injector.
• Clean or service the cylinder 7 injector if deposits are found and the design permits service.
• Replace the cylinder 7 injector if testing confirms out-of-specification flow.

Can I keep driving?

With a steady light and no marked roughness, drive only as needed and gently until it is diagnosed; continued miscombustion can raise emissions and harm the catalytic converter. Stop if the light flashes or the engine develops severe vibration or unsafe power loss.