My mum has recently got a 159 2.4jtdm
I wish my mum was that cool!!!!!
It sounds like you know what you're after so, I am sorry if any of this sounds patronising - it's just that you posted a pic of a black GT and they have bad memories for me - some dude ran me ragged in trying to sell me his - not at all a nice experience and the car was poo - walked away in the end - ANYWAY:
1) Make sure ALL of the electrics work. There is a buzzer that can be set to pick up on any button presses so make sure it works for all the buttons!!! And make sure the odometer display is not blinking.
2) Clutch is hard to depress and creaks - can be a sign of master cylinder on its way out.
3) Low mileage examples of a 2005/2006 model - could cause turbo problems with the cake up of carbon on the vanes - particularly if you're going to remap and put extra pressure on the turbo - albeit on occasion - expect to refurb the turbo.
4) 2004/2005/2006 - probably suffer to a greater degree of oil cooler pipe corrosion than newer ones - just because of age - can lead to a massive oil leak - and you really do not want it happening whilst you're driving!!! expect to pay £300 or so to replace both pipes and the cooler.
5) EGR valve - can play up but it's an easy clean and/or refurb or you can replace yourself (very easy and I am crap with the spanners!!!)
6) wobbly gear lever - yep, "just the bushes" - but the exhaust has to be removed to get the stick out...which comes out from underneath only - time consuming and pricey.
7) Suspension and wheels - if you get 18's, beware of potential flat spots on the wheels and be prepared for a hard ride - get a smooth road and the car is like a new car!!!! Get ready for some pothole swerving lad!!!
8) Try for a 55 plate - the 55 plate is the last model (ish) WITHOUT injector valves (swirl flaps). If you get a 55 plate, you might be lucky enough to get a "newer" engine with the "older" inlet manifold (which does not have the valves).
9) Clutches have been known to be changed pretty early - not that they need them, it's a case of mistaken identity with master cylinder/slave cylinder/gearbox actuator sticking (actuating arm is an easy DIY fix).
10) Just make sure it has excellent history and has been well looked after with a cambelt and
water pump change - if the water pump has not been done, be prepared for another £300 (at autolusso - who are FANTASTIC) to get the belt and pump done again (see if you can find anyone who come as highly recommended as them to do the pump and belt for less - dare you!!!)
11) Just make sure you take your time and don't just jump at the 1st one - I know this probably sounds really patronising but it's the best piece of advice i have been given - GTs are stunning and it is all too easy to get taken in by the looks
12) Why get one that has already been remapped? Get a good one, that is excellent, even if you have to max your budget and enjoy it as it is - save up and have it remapped yourself - at least you're sure it's been done properly on a car that wouldn't have had the knackers ripped off it to begin with!!!
Again, sorry if it all sounds elementary but I am just passing on what people have told me and I don't want you to get stung as you say you did with the 159.
Happy hunting fella. I hope you get a good one - they are FABULOUS cars.