P0208

What it means

P0208 means the engine control unit has detected a fault in the electrical circuit that controls the fuel injector on cylinder 8. The ECU monitors the injector driver and its wiring, and it sets the code when the current or voltage does not match what it expects, such as an open circuit, a short or a failing coil. This is a circuit fault rather than a fuel flow fault, though a dead injector will still cause a misfire.

Symptoms

• Engine management light on, possibly flashing if a misfire is present
• Rough running or a noticeable misfire, worse at idle
• Loss of power and poor acceleration
• Hard starting or extended cranking
• Increased fuel consumption
• Smell of unburnt fuel from the exhaust

Possible causes

• Faulty cylinder 8 injector (open or shorted coil winding)likely
• Damaged, chafed or corroded wiring between the ECU and the cylinder 8 injectorlikely
• Poor connection at the injector plug or a loose, corroded terminallikely
• Shared power supply or fuse fault affecting the injector circuitpossible
• Injector driver fault inside the ECUrare
• Water ingress or heat damage to the harness near the enginepossible

How to diagnose

1. Read all stored and pending codes and note the freeze frame data, including engine speed, load and coolant temperature when the fault set
2. Check for other injector circuit or misfire codes, especially on other cylinders, which may point to a shared supply or ECU issue
3. Visually inspect the cylinder 8 injector connector and harness for chafing, heat damage, corrosion, bent pins or a poor locking fit
4. Check the relevant fuses and relays that feed the injector circuit, using the wiring diagram for that model
5. Measure the injector coil resistance and compare it with the manufacturer specification for that engine
6. Check the supply voltage and ground at the injector connector, then test the control wire for continuity and shorts to power or ground
7. Use a scan tool function or a suitable test lamp or meter to confirm the ECU is pulsing the injector during cranking
8. Swap the injector with a known good cylinder, where access allows, to see whether the fault follows the injector

How to fix

• Replace the cylinder 8 injector if its resistance or operation is out of specification, following the procedure for that engine
• Repair or replace damaged wiring and use proper crimp or sealed connections
• Clean or replace corroded or loose connector terminals, or renew the connector
• Replace the blown fuse or faulty relay once the cause of the overload is found
• Replace or repair the ECU only after the wiring and injector have been fully proven good, and then code and programme it as the manufacturer requires

Can I keep driving?

Nearby codes

• P0207GenericCylinder 7 Injector A Circuit
• P0209GenericCylinder 9 Injector A Circuit