Injector Circuit / Open - Cylinder 9
The P0209 code means the vehicle's onboard diagnostic system has detected: Injector Circuit / Open - Cylinder 9. This is a critical severity code.
- Keep driving?
- No — stop driving
- DIY difficulty
- hard
- Estimated cost
- $150 - $500 (fuel injector $80-$250; labor $100-$300)
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What Are the Symptoms of P0209?
- Check Engine Light on or flashing
- Cylinder 9 misfire causing rough running
- Noticeable power loss
- Engine vibration
- Unburned fuel in exhaust
What Causes P0209? (Most Likely First)
- Failed fuel injector on cylinder 9 Very High
- Open or damaged wiring in the injector circuit High
- Corroded or loose injector connector Moderate
- PCM injector driver failure Low
- Injector coil open or high resistance Low
Can I Still Drive with P0209?
No — stop driving. P0209 is rated critical severity. Continuing to drive in this state risks further damage — get it looked at before your next trip.
Frequently Asked Questions
Can I drive with code P0209?
No. A dead cylinder sends unburned fuel to the catalytic converter, risking converter damage. Have the vehicle towed to a repair shop.
What vehicles have a cylinder 9?
Cylinder 9 is found on V10 and larger engines, such as the Ford 6.8L V10, Dodge 8.0L V10, and exotic cars like the Lamborghini Gallardo and Audi R8 V10.
Are V10 injectors more expensive?
V10 injectors typically cost more due to lower production volume. Expect $80 to $250 per injector depending on the vehicle. Labor can also be higher due to the complexity of V10 engine layouts.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose P0209?
-
Confirm cylinder 9 misfire with a scan tool.
-
Measure injector resistance on cylinder 9 (11-17 ohms typical). Open circuit indicates a failed injector.
-
Check for pulse signal at the injector connector with a noid light during cranking.
-
Inspect wiring and connector for breaks, corrosion, or disconnection.
-
If wiring is intact and the injector tests good, check the PCM driver output.
Sources 2
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines the generic OBD-II code ranges)
- Cross-checked against the SAE J2012:2002 DTC table (2026-08-27)archived scan of the SAE standard — readable copy, not SAE’s current edition
Which Vehicles Commonly Get P0209?
- 2003-2014 Ford F-250 (6.8L V10)
- 2004-2010 Dodge Ram 2500 (8.0L V10)
- 2007-2016 Ford E-Series (6.8L V10)
- 2005-2013 Lamborghini Gallardo (5.0L V10)
- 2010-2018 Audi R8 (5.2L V10)
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