Alfa Brera Error Codes Causing Emissions Test Trouble

I dealt with a similar issue on my 2009 Alfa 159 with the 2.2 gasoline engine. As someone with low experience working on cars, I mainly relied on professional help for this. The onboard diagnostics showed multiple stored codes after a computer reset. The check engine light kept coming back even after clearing the codes. This happened because the drive cycle hadnt been properly completed to set all system readiness monitors. The key was understanding that after any diagnostic system reset, the car needs to complete specific driving patterns. My workshop explained this was necessary for the exhaust system and emissions monitoring to be properly evaluated by the cars computer. The solution cost nothing since it just required driving the car in a specific pattern: Driving at steady highway speeds, Several start and stop cycles, Letting the engine idle, Gradual acceleration and deceleration After about 100km of normal driving, all monitors were set and the system was ready for emissions testing. Could you share your Breras engine size and specific error codes? This would help determine if youre dealing with the same readiness issue or if theres potentially another problem that needs attention.

Latest service was at 65000km, about 2 months ago. I followed the suggested driving cycle protocol for my Brera after the codes were cleared, but my onboard diagnostics still shows system readiness issues after 300km of mixed driving. Unlike your situation, my check engine light has started flashing intermittently during acceleration. The exhaust system seems to run rougher than usual, and Im getting p0300 and p0303 codes now. These are different from my original stored errors. Im thinking it might be ignition coils failing rather than just a readiness monitor issue. Will try swapping coils between cylinders next weekend to pinpoint if thats the actual problem before the emissions test. Has anyone else encountered similar OBD readiness problems combined with misfires in their Brera? The rough running is definitely worse when the engine is cold.

Thanks for the update on your Brera situation. On my Alfa 159, I initially thought I was dealing with just system readiness issues too, but ended up facing similar misfire symptoms. The flashing check engine light during acceleration combined with P0300 and P0303 codes strongly points toward ignition system problems, which matches what I experienced. Your plan to swap coils between cylinders is exactly what helped diagnose my issue. When I did the coil swap test, the misfire followed the moved coil, confirming it was indeed a failing ignition coil rather than system readiness. The rough cold running is particularly telling, this was identical to what I experienced before replacing my coils. A few key observations from my experience: Car diagnostics showed both readiness and misfire codes, Cold start performance was notably worse, Exhaust system sounded different due to the misfires, Computer reset alone didnt solve the underlying issue The good news is ignition coils are a straightforward fix. Once I replaced the faulty coils, both the misfires and readiness issues resolved after completing a proper drive cycle. This should get you past the emissions test without issues. Remember to clear the codes after replacing any parts to reset the system readiness monitors.

The coil swap test confirmed the misfire is following the coil position, so at least that narrows down the problem. I ordered a set of new ignition coils since the original ones have been in there since 65000km. Makes sense they might be wearing out now. The vehicle inspection guidelines in my manual mention needing all readiness monitors set before the emissions test, so hopefully replacing these coils will resolve both the misfires and get the onboard diagnostics back to normal. The exhaust system definitely sounds healthier when all cylinders are firing properly. Will update once I get the new coils installed and complete another drive cycle to check if the system readiness monitors reset correctly. Really appreciate everyone sharing their diagnostic experiences, saved me a lot of troubleshooting time by pointing me toward the ignition system rather than chasing sensor issues. Just hoping the parts arrive before my scheduled emissions test next week. Fingers crossed the cold start roughness goes away with the new coils.