Yep, totally agree with Heinz. The indirect injection Duratec is the reliable one! All sorts of reasonably priced upgrades available too.
The racing world still use this option and lotus fit it in the 7's The direct injection Gdi squirts the fuel straight into the cylinder head whereas in the indirect injection the fuel is introduced into the inlet manifold which results in several advantages, probably too boring to go into fully here but simply the backs of the inlet and exhaust valves are constantly washed by the fuel/air mix which cools the valves and also washes the backs of them keeping them clean so this engine doesn't suffer from gummed up valves. I'm not sure but think that not all Gdi engines have VVT, perhaps just the later or Ltd. edition options fitted with the Mazda variant. but you will have to check that one out yourself!
The Gdi variant was developed for Ford America from the reliable and bombproof Duratec 2.0L and was fitted with a turbo charger, it quickly became known as the worst engine ford had ever made however in all fairness the non turbo version is better but! there are many cases of gummed up valves with as little as 3000 miles on the clock and its not a simple quick fix! and will become a regular expensive service issue. Many owners claim theirs is fine then they have a look and get a big shock.
Most of the crap causing this issue is from the Breather system and primarily from the crankcase breather which along with the rocker box breather is directed back into the inlet manifold where negative pressure helps to suck them back into the engine to be re-burnt helping to control emissions. directing the crankcase breather through a filtered oil catch system might help but it seems the jury is still out as the whether or not it still requires the negative pressure provided by the inlet manifold.. This would dictate whether or not you could then vent the crankcase to atmosphere after the filter or if the crankcase needs to have the aided vacuum, returned to the inlet manifold.
A vent to atmosphere might also cause an MOT issue so should be easily reversed back! New or low milage engines don't usually suffer with engine blow by and it seems that introducing a catch can system to the rocker box vent is probably a waste of time unless you are constantly working the engine hard such as in racing.
