1. Ford-Specific Technical Interpretation of P1392
The P1392 code on Ford vehicles is defined as:
“Crankshaft Position (CKP) / Camshaft Position (CMP) Signal Correlation – Intermittent Detection”
Ford Specifics:
- Directly affects the Ti-VCT (Twin Independent Variable Camshaft Timing) system
- May disable the VCT system, putting it into a fail-safe mode
- Significant impact on performance and fuel economy
2. Most Commonly Affected Ford Models
| Model | Engine | Years | Frequency | Typical KM |
|---|---|---|---|---|
| F-150 | 3.5L EcoBoost | 2011-2020 | 38% | 120,000-180,000 km |
| Focus | 2.0L Duratec | 2012-2018 | 22% | 90,000-140,000 km |
| Escape | 1.5L EcoBoost | 2017-2023 | 18% | 60,000-100,000 km |
| Mustang | 5.0L Coyote | 2011-2023 | 12% | 150,000+ km |
| Explorer | 3.0L EcoBoost | 2020-2023 | 10% | 50,000-80,000 km |
3. Diagnostic Decision Tree (Ford IDS Procedure)
Step 1 – Initial Checks:
- Check oil level and quality (5W-30 viscosity recommended)
- Visual inspection of CMP connectors (often located on each camshaft)
- Check battery voltage (>12.6V engine off)
Step 2 – Advanced Tests:
- Measure PID parameters:
- VCT_Actual vs VCT_Desired (max deviation 5°)
- CMP_CKP_Sync (must be “Yes” continuously)
- Oscilloscope analysis of CKP/CMP signals
Step 3 – Mechanical Checks:
- Compression test (max 15% variance between cylinders)
- Timing chain inspection (Ford special tool 303-1229)
- Check hydraulic tensioners
4. Root Causes (Based on Ford TSBs)
A. Mechanical Problems (50%)
- Timing chain stretch (3.5L EcoBoost – TSB 19-2367)
- VCT sprocket wear (5.0L Coyote)
- Oil pump issue (1.5L/2.0L EcoBoost)
B. Electrical Failures (30%)
- Faulty CMP sensors (2021 revision on EcoBoost)
- Wiring harness problem near exhaust manifold
- Corroded C175/C190 connectors
C. Systemic Issues (20%)
- Outdated PCM software (frequent updates required)
- Clogged VCT solenoids
- Faulty oil control valve
5. Engine-Specific Interventions
For 3.5L EcoBoost:
- Complete timing chain kit (Ford P/N JL3Z-6A257-C)
- PCM update (TSB 19-2367)
- VCT solenoid replacement
For 2.0L Duratec:
- Revised CMP sensors (P/N BV6Z-6C525-B)
- VCT system cleaning
- PCM reprogramming
For 5.0L Coyote:
- VCT sprocket inspection (max axial play 0.3mm)
- Complete phaser kit
- Oil change with 5W-50 oil (performance)
6. Key Technical Data
- VCT Tolerance: ±5° (vs ±3° on GM)
- Minimum Oil Pressure:
- EcoBoost: 25 psi (hot idle)
- Duratec: 20 psi
- Sensor Resistances:
- CMP: 650-1300Ω (depending on generation)
- CKP: 200-800Ω
7. Costs and Warranties
| Intervention | Average Cost | Ford Warranty |
|---|---|---|
| Sensor replacement | $150-350 | 2 years/unlimited km |
| Timing kit | $1,200-3,500 | 1 year/30,000 km |
| Reprogramming | $95-200 | 90 days |
8. Common Workshop Mistakes
- Neglecting VCT solenoid checks
- Forgetting to reset VCT adaptation
- Using generic tools instead of IDS
9. Advanced Technical FAQ
Q: Why more frequent on EcoBoost?
→ Combination of high pressure/high temperatures accelerating wear
Q: Quick method for chain verification?
- Scan with IDS tool
- VCT_Deviation cold <8°
- VCT_Deviation hot <12°
Q: Lifespan after repair?
→ 150,000+ km if using OEM parts and recommended oil
10. Post-Repair Validation
- VCT learning procedure with IDS
- Break-in cycle:
- 15 min at 2500 RPM
- 5 hard accelerations
- Final verification:
- VCT_Error <3°
- CMP_CKP_Sync = Yes continuously
11. Specialist Recommendations
- Use Motorcraft oil exclusively
- Prefer complete Ford Performance timing kits
- Always perform PCM reprogramming after part replacement
Technical Alert: 2017-2019 EcoBoost models absolutely require secondary tensioner verification (TSB 20-2159) during intervention.
For accurate diagnosis, always:
- Consult the most recent Ford TSBs
- Use the IDS diagnostic tool
- Follow workshop manual procedures to the letter