Injectors replaced - more troubles on the way

nissan
altima

#1

The deal:

last year noticed a gas smell everytime I started the car - took it to the dealer two times - nothing found. Then a noise started. Turn out to be a blow gasket. Extended warranty covered everything just in time - new block engine in place now.

This year - after scheduled oil changes, I still noticec the gas smell once in a while, and car runs rough sometimes, with worse gas mileage than before engine replacement. Finally decided to do a general check up. NOW, they find that fuel injectors were going bad, thus a the poor gas mileage and smell - but NOW the warranty has expired.

So, am I entiled to get this repair for free? I got it done already - yeah I know, and actually it got worse - on the second day after returning from the dealer, car started making some clunking noise , coming for sure from the engine, and even stalled on a stop light. Is now back at the dealer to find out what is going wrong with it.

Aside this last issue, can I, should I, reclaim the reapris as " they should have been done under the warranty" as I took it to the shop complaining about issues, that now they even saiy that were the cause for my previous complains?(gas smell, and later a poor gas mileage)

Small claims Court?

Just a pep-talk with service manager and main boss about it, for getting reimbursed?

Thanks for the imput, and I apologize for the looong question