I've never heard a good word spoken about the JTS engine, but plenty of bad.
Basically a good engine ruined, they are not pleasant to work on, and many are producing nowhere near the stated power output.
It was always a given that despite any other failings an Alfa would always have a decent engine of some character... the JTS changed that unfortunately.
There are plenty of problems, but to say that there's never been a good word said is very much an overstatement. Plenty of owners (including me) like them when they're working, and some even favour its characteristics over the TS. I can't comment as I've never driven a TS.
IMO, the problems are related to it being an early implementation of direct injection, without many lessons learnt. It also cost Alfa a lot of money to produce (per engine) so it's possible that they tried to save money on stuff like the wiring looms that aren't brilliant.
For simple economic reasons, if you have two similar cars, one with a TS and one with a JTS, take the TS. Me, I wouldn't go back to an earlier 156 to get one - I'd rather stomach the unofficial 50k miles injector service interval.
Anyone give me an idea of working on one...usual stuff ..maintenance...whats not to like?
anything a pig.. could you maintain one yourself easily enough?
Injectors. Inlet manifold off, PITA.