Would you use an engine flush such as Forte in a 130TDi

[Brind]

I've had my car since September last year and so far it's had two oil changes in my ownership. I've done less than about 10,000 miles in total.
One done at my friendly garage and the last one I did myself with Castrol Edge 5w 40. I suppose like most diesel vehicles, it was pitch black within seconds of being churned up in the engine. I sucked out the old oil from under the filter too but it was still jet black after.
The car has covered 176,000 miles so it's of no wonder really that it's filthy inside.

I'm just debating whether to put forte engine flush in it next time and drive it for five minutes and then change the oil and of course, the filter. Most people seem to be against using flushes in higher mileage engines so I too am a little dubious!

She is quite smokey when cold, especially when you floor it in third when warm, in fact it's quite bad then! I can't work out the colour as I drive a lot at night. I'm not sure what oil was put in by the garage because it was far less smokey when they did it than when I put in Castrol Edge. In fact next time I will use Quantum as I can't say I'm very pleased with the Castrol at all! Since using it, it sounds a little tappy when revved high and lumpy and noisy when started from stone cold. It was never like this on the previous cheaper oil (of whatever make they used).
It's probably got the same old glow plugs too. I haven't tested them but will at some point.

It doesn't seem to use any oil in 5,500 miles. No idea if checked in longer intervals.

So, to flush a PD or not to flush a PD?