I am at last ready to buy one of these monsters. So, i am looking to all the experts on here to find out what are the BAD points of GTO twin turbos i should look out for when i go to test and buy. I have my eyes on a J Reg Japanese import which on the face of it seems a good buy. But like all of these types of cars, i am sure they have their Achilles heel…but i have no idea on GTO’s what that Achilles is.
Help appreciated.
Hi and welcome to GTOUK 
There’s is a really good buyers guide on the site that will help you with some of the pitfalls to watch out for .
Main things now check for rust at the front and rear floor pans by the arches , factoring for a full cambelt kit if there is no recent proof of it being done .
These cars are not getting any younger so make sure everything on it works as it should do , if your not sure then walk away , don’t be drawn in by the looks .
There are some really good cars out there at the moment , but also some dogs being advertised at decent prices .
If you see something you fancy post it up we will help where we can , condition and history is what I would be looking for , mileage is irrelevant as a lot of imports came over with a magical mileage 
Craig 
Personally I would look for recent history, I went with mine just becouse the engine had been fully rebuilt and had the later 4 bolt engine with 3mm oil lifters done.
I went with mechanics over looks, mine was totally standard looking…bugger all worked, spoiler, ecs, air con but those things you can fix or del. Like Craig says just wish I had had a poke about under as I’ve now had a fair bit of welding in the place Craig says about.
Good luck and welcome to the nut house.
Dave
Welcome along. Not really much I can add to what’s already been said… 
We love these car mainly because of the wow factor and you will get that even when stood infront of a heap that has good paint,look at as many as possible after a while a good one will stick out like a sore thumb,dont take a sellers word for anything unless it can be backed up with evidence,good luck with your search and welcome to GTOUK.
Oil pressure gauges are reknowned for giving inaccurate readings - even from new…be wary of any vehicle who’s gauge shows a low reading on cold starting, as the engine may be liable to spinning a bearing. The resulting costs you will incur to rectify this can run into thousands! My engine has been rebuilt as a consequence of this feature - and on start up from cold following the rebuild, the oil pressure gauge now indicates a level almost up to the half way mark.
John.
They seem especially susceptible to rot underneath at the rear. Aside from the underbody panels there is a crash bar at the rear behind the bumper which can get into a real state. This can be an MOT failure if it or the area to which it attaches has significant corrosion.
Muck also accumulates in the front wings and can cause the front sill to rot out, although this is often missed as the bodykit hides it from the exterior. You can see it if you open the door and look at the gap below the hinge.
Other than that, anything on original turbos is likely to burn a little oil to some extent. If buying one that has had the power increased, make sure as a minimum that the fuel pump had been “hotwired” (12v from the battery rather than 7v or 12v (if you’re lucky) through the fuel pump relay & resistor setup). Anything claiming over ~360bhp should have uprated injectors (and fuel pump ideally).
Another Achilles heel is the drivers seat bolster LOL… They all wear badly so expect this to need some TLC unless it’s been done already (circa £100).
They are very heavy on the brakes so anything other than high quality disks will warp with hard use, causing steering wheel vibration under braking.
Probably the biggest problem with them is you never run out of things to spend money on, and will probably never get the car as perfect as you would like it to be! That said, it’s an old car that also happens to be very complex, so that shouldn’t be a surprise.
That’s about all that jumps to mind right now. There’s a good buying guide on here that covers a lot of the major topics.
As craig said read the buyers guide. And even take it with you when you view a car. Post up a link to the one you are interested in as someone might know it and be able to give you some info. I have a tastefully modified Mk1 one up for sale at the moment. PM me if you are interested and i will send you details. It is about to have a new cambelt/water pump etc. fitted as the waterpump has failed. So may be a couple of weeks before she is ready for a new home.
…post deleted by moderator …
Only fully paid up members can advertise cars for sale on the forum
Regards
Craig
Have a look here for my post. New waterpump and cambelt installed and working perfectly.