P0282 – Cylinder 8 Injector Circuit Low

P0282 is a diagnostic trouble code that points to a problem with one specific cylinder in your engine, usually labeled “Cylinder 8 contribution/balance.” In simple terms, the engine computer has detected that cylinder 8 is not pulling its weight compared to the others. This can be caused by a fuel injector issue, wiring fault, low compression, or even a software problem. If you’re noticing rough running, misfires, or a flashing check engine light, this guide will walk you through what P0282 means, how serious it is, and how you can fix it.

What Does P0282 Mean?

P0282 is an OBD-II code that typically reads “Cylinder 8 Contribution/Balance” or “Cylinder 8 Injector Circuit Low.” Your ECU constantly monitors crankshaft speed and injector control signals. When it sees that cylinder 8 is not producing the same power as the others, or its injector circuit voltage is out of range, it sets P0282.

In practice, this code usually points to a fuel delivery or electrical issue at cylinder 8. On V8 engines, that’s often the rearmost cylinder on one bank, which can be harder to reach and more prone to wiring or connector problems.

Quick Reference

• Code: P0282
• Meaning: Cylinder 8 contribution/balance or injector circuit low
• Common Causes: Faulty injector, wiring fault, poor connection, low compression
• Typical Symptoms: Misfire, rough idle, loss of power, increased fuel use
• Severity: Moderate to severe – can damage engine or catalytic converter if ignored
• Fixes: Injector replacement/cleaning, wiring repair, coil or compression-related repairs

Real-World Example / Field Notes

In the shop, I see P0282 most often on higher-mileage V8 trucks and SUVs. A common scenario: the customer complains of a rough idle, poor towing power, and a flashing check engine light under load. Scan data shows misfires on cylinder 8 and code P0282 stored. After a quick coil and plug swap test, misfires stay on cylinder 8. Pulling the connector reveals a slightly green, corroded terminal at the injector. Cleaning and re-pinning the connector, plus a fresh injector, usually brings the engine back to a smooth, strong idle with no more codes.

Symptoms of P0282

• Rough idle: Engine shakes or feels uneven, especially at stoplights.
• Misfire under load: Hesitation, stumbling, or jerking when accelerating or towing.
• Loss of power: Noticeable drop in performance, especially on hills or highway merges.
• Increased fuel consumption: You may find yourself filling up more often than usual.
• Check engine light: Steady or flashing MIL, sometimes with additional misfire codes.
• Fuel smell or rich exhaust: Unburned fuel in the exhaust if the cylinder is not firing correctly.
• Engine vibration: More pronounced vibration felt through the steering wheel or seat.

Common Causes of P0282

Most Common Causes

• Faulty cylinder 8 fuel injector: Internally clogged, shorted, or open injector causing low fuel delivery or incorrect circuit resistance.
• Injector wiring or connector issues: Broken wires, poor crimp, corrosion, or loose terminals at the injector or ECU.
• Ignition-related misfire (on some systems): Weak coil, worn spark plug, or damaged plug wire causing cylinder 8 to contribute less power.
• Low compression in cylinder 8: Worn rings, burnt valve, or head gasket leak reducing cylinder efficiency.
• ECU driver fault: Less common, but the ECU’s internal injector driver circuit for cylinder 8 can fail.

Less Common Causes

• Fuel pressure issues: Marginal fuel pump or clogged filter affecting cylinder 8 more noticeably.
• Intake manifold leaks near cylinder 8: Vacuum leak leaning out that cylinder.
• Aftermarket tuning or modifications: Poorly calibrated tunes, big injectors, or engine swaps confusing contribution/balance logic.
• Mechanical timing problems: Stretched timing chain, slipped cam phaser, or valve timing issues affecting that bank.
• Contaminated fuel: Water or debris that partially clogs one injector more than others.

Diagnosis: Step-by-Step Guide

To properly diagnose P0282, you’ll want a basic scan tool (preferably with live data), a digital multimeter, a noid light or test light, and possibly a fuel pressure gauge. Access to service information for your specific engine (cylinder numbering, wiring diagrams, and injector specs) is very helpful.

1. Confirm the code and check for companions: Use a scan tool to read codes. Note any misfire codes (P0308), other injector codes, or fuel trim issues. Clear codes and see which ones return.
2. Visual inspection of cylinder 8 area: Locate cylinder 8 using a service manual. Inspect the injector connector, wiring harness, and nearby components for rubbing, burns, or oil contamination.
3. Check live data and misfire counters: Look at misfire data and fuel trims. Cylinder 8 should show higher misfire counts if it’s the main problem. Short-term trims may be elevated if the ECU is trying to compensate.
4. Injector electrical tests: With the key off, unplug the injector and measure resistance with a multimeter. Compare to spec and to another known-good injector. Out-of-range resistance suggests a bad injector.
5. Check injector pulse: Use a noid light or test light plugged into the injector connector while cranking or idling (follow safety procedures). A missing or weak pulse indicates a wiring or ECU driver issue.
6. Wiggle test the harness: With the engine idling, gently move the wiring harness and connector for cylinder 8. If the engine stumbles or clears up, you likely have an intermittent wiring or connector fault.
7. Swap components when possible: On some engines, you can swap injectors between cylinder 8 and another cylinder. If the code or misfire follows the injector, the injector is the culprit.
8. Check ignition and compression: If injector and wiring check out, inspect the spark plug and coil (if applicable) for cylinder 8. Perform a compression or leak-down test to rule out mechanical issues.
9. Advanced checks (Mode $06): Some scan tools allow Mode $06 data, where you can see contribution/balance or misfire counts per cylinder in more detail to confirm your findings.
10. Evaluate ECU if all else passes: If injector, wiring, ignition, and compression are all good, an internal ECU driver fault may be left. This is rare and should be confirmed carefully before replacing the ECU.

Pro tip: Always fix any obvious wiring or connector problems before throwing parts at the car. Many P0282 cases are solved with a simple re-pin, solder repair, or connector replacement instead of a new injector.

Possible Fixes & Repair Costs

Repairs for P0282 depend on what you find during diagnosis. A basic wiring repair or connector replacement can be relatively inexpensive, often in the $100–$250 range at a typical shop. Replacing a single fuel injector usually runs $200–$500 parts and labor, depending on access and whether the intake manifold must come off. If you’re dealing with ignition components, a coil and plug on one cylinder might cost $150–$350. Mechanical issues like low compression, valve problems, or head gasket failures are much more expensive, often $800–$2,500 or more. Labor rates, vehicle make, and parts quality all affect the final bill.

Can I Still Drive With P0282?

You can sometimes drive short distances with P0282, but it’s not recommended for long or hard use. A misfiring or underperforming cylinder sends unburned fuel into the exhaust, which can overheat and damage the catalytic converter. You’ll also have reduced power and possibly unsafe drivability when merging or towing. If the check engine light is flashing, that’s the ECU warning you that catalytic converter damage is likely, and you should stop driving and address the issue as soon as possible.

What Happens If You Ignore P0282?

Ignoring P0282 can turn a relatively simple injector or wiring repair into a much bigger problem. Persistent misfires can melt the catalytic converter, foul spark plugs, wash down cylinder walls with fuel, and accelerate wear on pistons and rings. Over time, you may end up with low compression, higher oil consumption, and a much more expensive repair bill than if you had fixed the original fault early.

Last updated: January 22, 2026

Vehicles Commonly Affected by P0282

P0282 is most frequently seen on V8 engines where cylinder 8 is present. That includes many Ford F-150, F-250, and Expedition models, GM trucks and SUVs like Silverado, Sierra, Tahoe, and Suburban, as well as Dodge/Ram trucks and some Jeep and Chrysler V8 applications. It can also appear on European and Asian V8s (BMW, Mercedes-Benz, Lexus, Infiniti), though less commonly. High-mileage work trucks, tow vehicles, and performance cars with V8 engines tend to show this code more often due to heavier loads and heat cycling.