Monza engine misfires

Sounds familiar! I had similar symptoms in my Monza – rough idle, jerking acceleration, and the check engine light. I chased it for weeks, checking the fuel pump, cleaning the throttle body, and still couldn't nail it down. Did you notice any specific cylinder misfire codes? Mine threw codes for cylinder 3. I'm curious to know if you had that too.

I did get cylinder misfire codes! I think it was P0300 and P0304. You mentioned fuel pump and throttle body, but did you ever get any codes indicating a lean condition? Anything else I should check before I take it to the shop?

Okay, P0300 and P0304 are definitely pointing towards misfires. I did check for lean conditions but never found anything conclusive. I eventually traced my issue to a faulty fuel injector. After swapping it out, the problem vanished instantly! Given your symptoms and the codes, I'd suggest having your injectors checked. It might be time to let a mechanic take a look.

Thanks a lot for the advice! I took it to my local workshop and, as you suspected, a defective injector was the culprit. Cost me 515€, but at least it's fixed. Really appreciate you pointing me in the right direction!