VEHICLE: 2012 Audi A3
ISSUE: Engine stalls immediately after starting when vehicle parked overnight
DIAGNOSIS & SOLUTION:
We are struggling to diagnose a fault on a 2012 Audi A3 1,4 TFSI. In very cold ambient air temperatures the engine stalls immediately after starting when the vehicle is parked overnight. The engine starts and runs fine after the car has been parked in the workshop for several hours. We have carried out some basic checks on the air and fuel systems and checked for any stored trouble codes, none were present. Have you heard of this fault?
Yes, we have been made aware of this fault in countries with cold climates. The fault affects A3 models with CAXC/CMSA engine codes. There is condensation build up in the rear exhaust silencer that freezes overnight and prevents exhaust gas flow. To prevent water build up in the rear exhaust silencer, drill a water drain hole. Make a water drain hole in the rear exhaust silencer with a 5 mm drill using the following measurements: fig 1.1. = 86 mm, fig 1.2. = 273 mm, fig 1.3. = 5 mm. This should rectify the fault.