OBD-II Code P0208 — What It Means & How to Fix It

What Does This Error Mean?

P0208 means the PCM found an electrical fault in the fuel injector circuit for cylinder 8. This only affects V8, V10, and larger engines. The problem may be a bad injector, damaged wiring, or a corroded connector. A misfiring cylinder 8 can overheat and destroy your catalytic converter.

Affected Models

All 1996+ vehicles with 8 or more cylinders
Common in Ford 4.6L, 5.0L, and 5.4L V8 engines
Common in GM 4.8L, 5.3L, and 6.0L V8 trucks
Common in Dodge Hemi 5.7L and 6.4L V8 engines
Common in Jeep Grand Cherokee V8 models

Common Causes

Internally failed fuel injector on cylinder 8 with an open or short circuit
Wiring harness damage from heat, rubbing, or physical impact near cylinder 8
Loose, corroded, or melted injector connector on cylinder 8
Severely clogged injector with abnormal resistance reading
Rare PCM injector driver failure for the cylinder 8 circuit

How to Fix It

Find cylinder 8 using a firing order diagram for your specific engine. On GM V8s, cylinder 8 is on the passenger side rear. On Ford V8s, it is on the driver side. Verify your specific layout before starting work.

Cylinder numbering differs between manufacturers. Using the wrong diagram is a very common mistake that wastes time.
Disconnect the cylinder 8 injector connector. Measure the injector resistance with a multimeter on the ohms setting. A healthy injector reads roughly 11-17 ohms. Zero or infinite resistance confirms an electrical failure in the injector.

The exact specification varies by vehicle. Look it up in your service manual for the most accurate result.
Inspect the injector wiring harness from the connector back toward the PCM. Cylinder 8 is typically at the rear of the engine, where harness routing often passes close to hot exhaust components. Look for melted insulation and broken wires.

Rear cylinders on V8 engines are notorious for heat-damaged injector wiring. This is a common root cause.
Swap the cylinder 8 injector with a matching injector from another cylinder. Clear all fault codes and drive the vehicle. If the code moves to the cylinder that received the old injector, the injector is confirmed faulty.

Only swap injectors that are the same part number. Mixed injectors can cause fueling problems in both affected cylinders.
Install a new injector with a fresh O-ring lubricated with clean engine oil. Reinstall the fuel rail, torque all fasteners to spec, and clear stored fault codes. Test drive and confirm the check engine light stays off.

If the vehicle has over 100,000 miles, consider having the remaining injectors cleaned or tested at the same time.

When to Call a Professional

If the code follows the injector when you do a swap test, the injector is defective. If the code stays on cylinder 8 no matter what, the wiring or PCM needs professional attention. A technician can check the injector driver waveform with an oscilloscope. Diagnosis runs about $80-$130. Injector replacement is typically $150-$400 per cylinder depending on the engine.

Frequently Asked Questions

Can I drive with P0208?

Short trips are possible but not recommended. A cylinder not firing sends raw fuel into the exhaust. This overheats and damages the catalytic converter quickly. Catalytic converter replacement costs $800-$2,000 or more. Fix the injector circuit problem soon.

Is P0208 more common on high-mileage engines?

Yes, it is more common on older, higher-mileage vehicles. Injector internals wear out over time. Wiring insulation also deteriorates with age and heat exposure. Vehicles over 100,000 miles are at higher risk for this type of fault.

Could the PCM cause P0208?

Yes, but it is uncommon. The PCM contains individual driver circuits for each injector. If the cylinder 8 driver fails, no signal reaches the injector. A good technician can test the PCM output directly. Exhaust all other possibilities before assuming the PCM is at fault.