rail pressure too high
 

what a long evening that turned into... after doing a bit of driving... I filled up car with diesel after being very quite low on fuel.....10 mins later car dies, aa come out and diagnose it with rail pressure too high..
engine sounds rough as arseholes and he says he thinks its miss firing, after giving it a little rev smoke pours out the back.. not black tho.... get towed home and am still none the wiser as to what it is that's wrong.. a friend has said he think its most definite the fuel filter, but the wife google the rail pressure too high and it comes up with the fuel sensor ? help?

Change your fuel filter and all should be well.
Only use genuine Volvo or big German makes like Mann, Bosch, Mahle or Hengst.

ok so fuel filter changed ....still no better really.. thick white/grey smoke coming out the back on acceleration..still rough almost sounds like it is flooded..??
help?

What's the exact engine oil level and when was the oil last changed?
Is the area around the injectors bone dry?

Diagnostics live data could quickly rule out sensors.....

oil level is perfect and yes injectors are bone dry...

Ok, well as mentioned, diagnostics is really the next step, preferably using Volvo Dice and Vida.
That kind of running issue should show up as a data anomaly somewhere so pretty simple to start narrowing down.

hmm
 

ok so had been advised by a mechanic to put some red x fuel cleaner stuff in as he said it could have a blocked injector.. so have done that and driven round the block... still no better still smoking like a bitch and still lacking power and rough... also when parking it up on a slight hill it died again....has started since..
any ideas?

How many miles since you put the Redex in?

Diagnostics...... still.
Alternatively, find a better mechanic who'll approach the problem correctly.

If the rail pressure was/is far too high, it's possible that it's enough to overcome the seals in the injector and cause it, or that because the pressure is soo high, when the injector opens it's depositing way too much fuel in, resulting in smoke and poor performance.

You don't specify if you have the 163 or 185 engine.
I don't know about the 185, but on the 163 there is a fuel pressure control valve - I had to replace it on mine, I had the opposite problem with the pressure dropping too much and caused it to stall when pulling away.
VIDA showed this clearly, when monitoring the live data on a graph - but there was no fault code for it logged.