Some customers may complain about an unusual noise coming from the engine compartment for about 20 seconds...
Mazda technical service bulletin 01-011-20-3734 for 2012-2016 Mazda MAZDA3, 2013-2016 Mazda CX-5 and 2014-2017 Mazda MAZDA6 and others.
- Bulletin number
- 01-011-20-3734
- Component
- Engine and engine cooling
- Summary
- Some customers may complain about an unusual noise coming from the engine compartment for about 20 seconds after a cold engine start. This noise is a normal engine operation for improved exhaust gas emissions. The noise does not indicate a malfunction. ACCELERATED WARM-UP SYSTEM (AWS): All SKYACTIV-G engines adopt AWS to reduce exhaust gas emissions immediately after a cold engine start. AWS increases the engine idling speed and retards the ignition timing for about 20 seconds after the cold engine start to quickly warm up the catalytic converter. The customer may identify the engine sound during the AWS operation as a unusual noise.
Owners of these vehicles have filed 240 complaints in the engine category.
Vehicles covered
- Mazda MAZDA3 2012-2016 20122013201420152016
- Mazda CX-5 2013-2016 2013201420152016
- Mazda MAZDA6 2014-2017 2014201520162017
- Mazda MAZDA2 2016-2017 20162017
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