Fiat knocking POP
This bulletin applies to the 2012 Fiat 500 Abarth POP models, equipped with the 1.4L turbo engine, built before May 9, 2012.
Customers may experience an engine knock sound when the vehicle is driven aggressively with “regular” fuel (less than 91 octane). This condition begins to occur at low engine speeds with high boost pressure and high exhaust gas temperatures, particularly with hot ambient temperatures.
A MIL on with DTC P0441 (EVAP purge system performance) and P0128 (thermostat rationality) may be set active or stored.
Updating the PCM software will correct the conditions.
Using a scan tool (wiTECH w/Smart Cable 410) and appropriate diagnostic procedures available in TechCONNECT, verify that all engine systems are functioning as designed. If DTCs are present other than the ones listed earlier, record them on the repair order and repair as necessary before proceeding.
Install a battery charger to ensure that battery voltage does not drop below 13.2 volts, and do not allow the charging voltage to exceed 13.5 volts during the flash process.
- Reprogram the PCM with the latest software, Follow the detailed service procedures available in DealerCONNECT/TechCONNECT. Refer to Group 8 – Electrical > Electronic Control Modules – Service Information > Module – Powertrain Control > Standard Procedures > PCM/ECM Programming.
- After PCM programming, turn the ignition key to the OFF position for a minimum of 60 seconds to allow the module tp update and power down.
- Turn the key to the ON position.
- Using wiTECH, at the home screen select PCM.
- Is the vehicle equipped with a manual transmission?
- If Yes >>> DTC P1302 – Transmission Self learning will be present. Depress the clutch fully to allow this DTC to store, then proceed to Step 6.
- If No, the DTC will be stored automatically.
- Perform Cruise Control Learn by pressing and holding the ON/OFF button on the steering wheel until the cruise indicator illuminates.
- Turn the ignition key to the OFF position for a minimum of 60 seconds to allow the module to update and power down.
- Using wiTECH, clear any DTCs that may have been set in all modules due to reprogramming. The wiTECH application will automatically present all DTCs after the flash and allow the technician to clear them.
- Start the engine and verify that no DTCs are set.
- Type the necessary information on the Authorized Modification Label and attach it near the VECI label.