Hi guys
Been trying to get to the bottom of a spluttery idle I’m having in my 1kzte hilux surf, and really hoping someone here can help,
whenever the car Is cold it will start up reasonably good after a couple of cycles of the glow plugs, will idle perfectly normal for the first 20-30 seconds then the revs will drop slightly and will start missing and spluttering which produces a whistle sound and a grey smoke out the exhaust, once car is warm it goes away and won’t do it again but I have noticed that it is lacking low down torque and fuel consumption is very high, puts a grey/black haze of smoke out the back when under load.

Things ive replaced so far;
new head (20,000km ago)
replaced water pump, thermostat all new belts, new radiator, New glow plugs, New injectors, new fuel filter/ lifter pump, all new fuel lines and clamps.

I have a video of what it’s doing but haven’t quite worked out how to post it up, My instinct is it could be the injector pump but after seeing the price of a new one I really hope it isn’t,
any help would be greatly appreciated
thanks
Callum