P0203 on Ford: How to Diagnose & Fix
Injector Circuit/Open - Cylinder 3
2 Ford models · 2 documented issues · 1 critical · $300-$2,500 repair
P0203 on Ford by model: symptoms, diagnosis and fix
The 2017-2023 Ford Transit with the 2.0L EcoBlue diesel engine (available in some markets) and the 3.5L EcoBoost V6 experience fuel injector failures causing rough running, misfires, poor idle, reduced performance, and excessive smoke on cold start. Parkers UK documents an official Ford service action for Transit EcoBlue diesel injector failures traced to a quality issue with Continental-supplied injectors where an internal surface coating comes unstuck, blocking the injector. FordTransitUSAForum.com documents injector failure on 3.5L EcoBoost Transit models as well, where direct injection fuel deposits cause injector spray pattern degradation. RepairPal estimates individual injector replacement between $266 and $627 depending on Transit model, but multiple injectors often need replacement simultaneously, and contaminated fuel systems can cost significantly more.
Common Symptoms
- Rough running and engine misfires
- Poor idle quality
- Excessive blue or black smoke on cold start
- Reduced engine performance and power
- Check engine light with injector or misfire codes
- Engine stalls immediately after starting
- High fuel consumption
- Engine hesitation under acceleration
How to Fix
For Transit 3.5L EcoBoost: replace failed injectors ($100-200 per injector, 3-4 hours labor). Consider replacing all 6 injectors if the vehicle has over 100k miles - if one has failed, others are likely close behind. For EcoBlue diesel: Ford issued a service action for Continental injector failures - check with dealer for coverage. Use only Top Tier gasoline and change fuel filters per schedule. Professional fuel system cleaning every 50,000 miles can extend injector life.
Sources for this issue (1)
The 7.3L diesel engines (IDI pre-1994, Powerstroke 1994+) experience injector failure causing rough running, hard starts, and excessive smoke. The IDI injectors are simpler mechanical units; Powerstroke uses HEUI hydraulic electronic injectors.
Common Symptoms
- Hard starting
- Black or white smoke
- Rough idle
- Knocking noise
- Loss of power
How to Fix
Sources for this issue (1)
P0203 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0203 mean on a Ford?
P0203 stands for "Injector Circuit/Open - Cylinder 3." This code means the Engine Control Module detected an electrical problem (open circuit or out-of-range resistance) in the fuel injector control circuit for cylinder 3. The ECM pulses each injector electrically and watches the circuit to verify it is operating. P0203 means the expected feedback for cylinder 3's injector is missing or abnormal, so that cylinder may not be fueling properly. The typical result is a misfire, rough idle, and reduced performance traceable to cylinder 3. On Ford it is documented across 2 models: Transit, F-250.
What are the most common causes of P0203?
The most common causes of P0203 are: Damaged or corroded injector connector at cylinder 3, Open or shorted wiring in the injector control circuit, Failed (electrically open) fuel injector on cylinder 3, Loose or backed-out connector pin, Poor ground or power feed to the injector, Faulty injector driver inside the ECM/PCM, Chafed harness causing intermittent open. The specific cause varies by vehicle.
How much does it cost to fix P0203 on a Ford?
Published repair estimates on Ford range from $300 to $2,500 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0203 on a different make?
View P0203 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.