ML Tirton wont rev past 2,000

[IdRatherBe]

Have a 3.2 lt Triton I bought about 4 months ago, been going great until last Friday where its started to miss (for want of a better word). Start it up no problem and it idles no problem, but when I rev it to about 2000-3000rpm thats where it stays, blows a lot of white smoke also when revving out but not at idle, can drive it no worries as long as I stick to gear change around 2000rpm. Once driven for say 15-20 minutes it comes good and will drive normal.

So not knowing diesels well I'm doing test as per a petrol engine, there in no water in the oil, no oil in the water, I can de-pressurize the radiator cap and then stick it back on and start the car and it doesn't pressurize straight away, so without a compression test I'm ruling out a head gasket

I've have a OBD2 scanner and Torque, no fault codes come up, checking fuel pressure it fine and increases pressure as revs go up.

Anything else to check, it's booked in for a service anyway this week, so fuel filter will be changed as oil and oil filter. Anything else can check before I take it in.

Thanks

[spot01]

Did you refuel just before it started mis-behaving?

If so, check for contaminated/incorrect fuel &/or water in fuel (is there any water in the water trap on the fuel filter?)