1. Specific Saab P1392 Interpretation
The P1392 code on Saab vehicles corresponds to:
“Desynchronization between the crankshaft position sensor (CKP) and camshaft position sensor (CMP) – Intermittent Error”
Saab Specifics:
- Particularly affects Turbo Ecopower engines
- Impacts the Trionic system (engine management)
- Can cause power loss and unstable idle
2. Affected Saab Models
| Model | Engine | Years | Critical Mileage |
|---|---|---|---|
| 9-3 | B205 (2.0T) | 1998-2011 | 120,000-180,000 km |
| 9-5 | B235 (2.3T) | 1997-2009 | 100,000-160,000 km |
| 9-3 | Z19DTH (1.9TD) | 2003-2011 | 150,000-220,000 km |
3. Main Causes (Based on Saab TSBs)
A. Mechanical Problems (55%)
- Timing belt wear (especially on B205/B235)
- Automatic tensioner failure
- Excessive timing gear play
B. Electrical Failures (35%)
- Faulty CMP sensor (ref. Saab 55559281)
- DIC connector problem (Direct Ignition Cassette)
- Damaged wiring near the turbo
C. Other Causes (10%)
- Oil pressure problem
- Partial Trionic module failure
- Improperly timed belt after service
4. Complete Diagnostic Procedure
Step 1 – Initial Checks
- Check timing belt tension
- Visually inspect CMP sensor (located on exhaust side)
- Check DIC condition and its connectors
Step 2 – Electrical Tests
- CMP resistance: 900-1100Ω (at 20°C)
- CKP signal: 0.5-3.5V AC (during startup)
- Continuity test of cables to ECU
Step 3 – Mechanical Checks
- Check timing mark alignment
- Check tensioner pulley condition
- Measure camshaft axial play
5. Engine-Specific Solutions
For B205/B235 (Turbo Gasoline)
- Complete belt kit (including hydraulic tensioner)
- CMP sensor replacement (improved version)
- DIC contact cleaning
For Z19DTH (Diesel)
- Complete timing system inspection
- Oil pump verification
- Injector control
6. Key Technical Data
- Belt tension: 45-55 N (new)
- Minimum oil pressure: 2.5 bar (hot idle)
- Belt interval: 80,000 km or 5 years
7. Estimated Repair Costs
| Service | Cost (EUR) | Duration |
|---|---|---|
| Sensor replacement | 150-300€ | 1h |
| Complete timing kit | 500-900€ | 4-6h |
| Electronic diagnosis | 80-120€ | 1h |
8. Common Mistakes to Avoid
- Using non-original belt kits
- Neglecting tensioner pulley replacement
- Forgetting to reset adaptation after repair
9. Expert Tips
- For B205/B235:
- Prefer Gates or INA kits
- Systematically check water pump during belt change
- For Z19DTH:
- Check belt tension every 30,000 km
- Use premium quality 5W-40 oil
- Recommended tools:
- Tech2 or equivalent for diagnosis
- Torque wrench for pulley tightening
10. Technical FAQ
Q: Is this code critical on Saab?
→ Yes, can cause combustion problems and damage the turbo
Q: Can I drive temporarily?
→ Maximum 50 km at moderate RPM to reach a workshop
Q: Recommended prevention?
- Preventive belt change at 80,000 km
- Using quality synthetic oil
- Annual timing system inspection
11. Conclusion
To effectively resolve P1392 on Saab:
- Thorough timing system verification
- Complete electrical system control
- Using original or equivalent quality parts
⚠️ Important: Saab Turbo engines are sensitive to timing. Intervention by a Saab specialist is strongly recommended. Always maintaining correct timing belt tension is crucial to avoid catastrophic engine damage.