Giulietta Diesel Misfire Causing Power Loss and Jerking

I had nearly identical symptoms with my 2014 Alfa Romeo MiTo diesel last year. The rough running, power loss during acceleration, and check engine light pointed to a combustion misfire, but the real culprit was a faulty fuel injector. The diagnosis revealed one injector was not spraying fuel properly, causing inconsistent fuel delivery and the jerking sensation. The fuel injector had carbon buildup and was beyond cleaning. This is a relatively common issue on these engines after 100k+ miles. The repair required replacing the defective injector and running a full system diagnostic to ensure proper fuel pressure from the fuel pump. While the labor was intensive since they needed to access the top of the engine, it was a necessary fix. Driving with a bad injector risks damaging other engine components. The fix resolved all symptoms, smooth acceleration returned, check engine light cleared, and proper power was restored. Most importantly, fuel efficiency improved significantly after the repair. If these match your symptoms, request they specifically check the fuel injectors and fuel delivery system. A reputable shop should be able to run injector performance tests to identify any failing units.

Thanks for sharing your experience! Your symptoms were exactly what I faced. After that rough throttle response and constant jerking during acceleration, getting it fixed was such a relief. Mine turned out to be a combustion misfire caused by a bad fuel injector coil. Quick question, do you remember roughly what it cost you for the complete repair? After my mechanic horror stories, I am extra curious about pricing now. Also, has everything been running smoothly since the fix or have you noticed any other issues pop up?

Thanks for asking about the costs. I paid 515 Euro for the complete injector replacement which fixed the combustion misfires detected by the diagnostic. Since getting it properly repaired, the engine has been running perfectly smooth with no rough idle or power issues. The fix totally eliminated that annoying jerking during acceleration and the check engine light has stayed off. The repair has proven to be worth every cent, no new problems have surfaced in the months since. The engine response is crisp again and it feels like a different car compared to when it was misfiring. Most importantly, I am seeing much better fuel economy now that the injection system is working correctly. My advice to anyone experiencing similar symptoms is to get the fuel system properly diagnosed right away. Ignoring injection problems can lead to more expensive engine damage down the road.

I took it to a trusted mechanic after getting that advice. The total bill came to 490 Euro for replacing the faulty injector and cleaning the entire fuel system. Really similar to what you paid and honestly worth every cent considering how well it runs now. The repair process was straightforward, they ran a full diagnostic that confirmed the engine misfiring was indeed from a bad fuel injector. They had it fixed within a day. No more check engine light, no more jerking during acceleration, and the engine purrs like new. Been driving it for about 3 months since the repair and absolutely no issues have come up. Fuel economy is noticeably better too. Such a relief after my previous bad experiences with mechanics. Sometimes you just need the right diagnosis and honest work to solve these problems.