Repair procedures (plant/service)
- Visual inspection of HFM plug contacts
- Check wiring between HFM and DME
- Check induction system/crankcase for leaks (the positive crankcase ventilation system can allow vacuum leaks with air from the crankcase entering the manifold, for instance, if vacuum line from brake booster to vacuum pump is leaking)
- Check for DISA diagnostic fault code entries and DISA control operation (DISA fault does not prevent HFM plausibility check)
- Carry out VVT travel limit initialization routine