📋 Article Index
🔧 MAIN CAUSES OF START FAILURE
1) Defective or incorrectly mounted MultiAir module
The MultiAir module controls valve lift via oil and electro-hydraulic actuators. If it is not bled properly or is defective, it can leave the valves open ⇒ zero compression.
- Faulty or incompatible module.
- Assembly without preload tool or oil bleeder.
2) Damaged wiring and connectors
The MultiAir communicates with the engine control unit via delicate wiring: oxidation or breakages generate errors.
3) ECU not synchronized
The control unit may become misaligned with the MultiAir, preventing starting.
4) Insufficient oil pressure
Without the correct pressure, the MultiAir won't work. Used or low-quality oils are one of the main causes.
5) Inaccurate engine timing
If the crankshaft pulley (not tapped) slips, the timing will be out of phase even when using the correct jigs.
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- OBD-II scanner to read error codes.
- Real oil pressure measurement.
- Check wiring and power supply continuity.
- Check the rev counter (CKP) and phase (CMP) sensors.
- Test the MultiAir module on another car.
💡 SOLUTIONS AND COSTS
| Intervention | Approximate cost |
|---|---|
| MultiAir purge and adaptive reset | €120 – €250 |
| Wiring check/repair | €80 – €150 |
| ECU update | €100 – €200 |
| Refurbished MultiAir module | €600 – €900 |
| New MultiAir module | €1,000 – €1,200 |
🛡 PREVENTION
- Oil service every 10–12,000 km with MultiAir specification.
- Inspect wiring and connectors every 2 years.
- Trust expert workshops on MultiAir systems.
❓ FREQUENTLY ASKED QUESTIONS
Why does the MiTo MultiAir have no compression after the cylinder head?
Because the module has not been bled properly: valves remain open ⇒ zero compression.
Can a used module work?
Yes, but it must be compatible and tested. A refurbished one with a warranty is preferable.
How long does the MultiAir last?
With regular maintenance it can exceed 150,000 km.
📌 CONCLUSIONS
Starting problems on the MiTo MultiAir often stem from incorrect oil , incorrect bleeding , or the module itself. With targeted diagnosis and reliable spare parts, these problems can be solved once and for all.
👉 Read also the complete guide on all MiTo faults: Alfa Romeo MiTo Problems: Common Faults and Solutions
Article updated by Gianni Tritella – workshop & auto parts. Based on real diagnoses.
