F355 Recall Campaign Question

I have the similar thing happening to my 355. After the fuel block recall is fixed by Ferrari of Silicon Valley a few weeks ago, I noticed the smell of something burning, not the smell of fuel. I am thinking it is due to the installation of the new parts such fuel lines, etc. getting burned a bit with the engine heat. But then again, they seemed to also fix the "Check the Engine" light, by which was originally casued by the test pipes having no O2 sensor. Could the smell be the smell of the exhaust? BTW, I had not driven the car for more than 2 weeks since the fix and could still smell the burning when I took the car for a short drive yesterday.