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Anyone have any idea on what the GTR is doing?

There is a few symptoms:

- exhaust temperature light is on(when it comes on it does the stuff below)

- on idle it struggles to stay at a stable rev and conks out

- when driving it feels like engine drops power for a split second (driving along it feels like tugging on the handbrake quickly) numerous time while the exhaust temperature light is on

Faulty sensor? But I didnt think the sensor does anything besides lighting up the dash light when the exhaust temp is too hot...

If I cant diagnose it I guess I'll have to leave it to the tuners to figure it out since I'm booked it for a dyno run touch tune etc anyways....

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Its got a de-cat pipe in there though... it even did it with the standard cat which I had on for Vehicle Inspections for awhile - didnt drive it around too much when I had that on.

It only did it a few times ever before I put the standard exhaust/cat back on for vehicle inspection(roadworthy) and then it seems to be more frequent ever since, even after I put the aftermarket more high flowing exhaust on with the de-cat pipe.

coilpacks and spark plug has been changed, injectors no...

Why would it only happen here and there and only briefly though when the exhaust temperature light is on?

Seems to be more worst today as I took it for a drive, come home park it up, went elsewhere in another car for about half hour come back turn it on and it started doing it nearly straight away and conked out, drove it down to the car wash and it conked out as I left it to idle and hose the car down, turn it on drove it home(its only a 1 minute drive per way), went into my driveway and turn it off as the engine was struggling to have a stable idle - then needed to move the car about 15 minutes late so turned it on and it was still doing it doesnt stay stable and wants to conk out unless I keep my foot down on the accelerator so the rev doesnt drop down enough to conk out.

check which light you are seeing and check what it means in the service manual before guessing the cause

there are two lights that come to mind

one is the ENGINE CHECK LIGHT or orange ENGINE logo

the other is the EXHAUST OVER TEMP or RED CAT LIGHT

which one are you getting and check what it says in the service manual

ie no point guessing AFM's coilpacks etc if it's the RED CAT LIGHT as that's the CAT TEMP sensor warning

given you have a powerfc when the light comes on, use the hand controller and read what it is telling you

for an online demo and what you should be looking for check out

http://www.paulr33.com/powerfc-emulator/menu.html

you want to goto ETC, SENSOR SW CHECK

and then with the online emulator, learn how to work out what is wrong

Ah the PFC hand controller - I totally forgotten about that, took it off for vehicle inspection.

I just hooked it up, turned it on and left it to idle and after awhile it started doing it again so I quickly jumped back into the car and on the hand controller "AF-1" was highlighted and dropped down to 0.00v...

because the 32 gtr only has a cat temp light, not a cat temp and engine check light :D it is PFC showing you an error, looks like youv'e found it already.

if you can't easily get your hands on another afm to try, swap the 2 around and see if the error now apears as AF2

Hope its just a really dirty AFM, which it was - and I've cleaned it out with some contact cleaner earlier. See how it goes tomorrow when I take it out to the tuners for a dyno run check up and tune.

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