Looking to clean the maf as soon as I work out How to remove it... Looking to give it a clean to try reduce black smoke on heavy acceleration and thought about the pcv also, is it easy to get to and remove / clean ? Haynes seems to suggest removing inlet manifolds and alternators as a minimum...?

Pcv valve on other cars ive worked on were right there infront of me, its only a valve that closes as the breather pressure rises to stop oil getting back into the inlet, basically a bit plastic and a spring, will have to have a look at what ford came up with, on cleaning Maf, dont use brake cleaner, electrical cleaner is ok but hold it a way so the liquid runs away from the electrical side of things.

There is no guarantee that the maf or PCV vanve is causing the smoke, it could be many other things, like the DPF, injectors, etc

Check that your (engine) oil level is going down, if it is not, its probably not the PCV valve that is the problem

The PCV (Positive Crankcase Ventilation ) valve is a simple plunger and spring that opens under certain conditions to release pressure from the crankcase into the inlet

It can become "gunged up" so the crankcase becomes pressurized, forcing engine oil into the inlet (hense the reason you would check your oil level - as the oil level would go down if you were loosing any)

If this happens you would be burning oil - you would smell it out of the exhaust ("burnt oil" smell) and the smoke would be a different colour from normal "diesel" smoke

If you have a DPF fitted the carbon/ soot can build up in it over time (especially if the engine has run rich for a while) so whenever you "boot" it it releases some of the soot in the DPF

i would be looking also for a boost leak in your boost hoses

The MAF sensor is located between the air box and turbine, genarally, they stay clean (depending where the breather comes in) and you dont get trouble from then, cleaning it may not make any difference

A catchtank could be fitted on the crankcase breather - it would "catch" ank oil coming out of the crankcase and help keep your inlet clean

Removing the alternator is a lot of hassle just to check/ clean something that may not need done

I remember you fitted a new air filter - did you fit an EGR blanking plate? / take the inlet manifold off to clean it?

Finally - some engines do not have PCV valves - i don't know if the 1.6 TDCI has one

Thanks for the replies fella's, I plan on getting the electrical spray from eurocar parts sometime this week, last time I looked at removing the sensor, I couldnt find a way to do it :p but as for the PCV I dont think I will bother.

FOCA, I did fit the EGR plate, and have had confirmation that my car does not have a DPF, so I dont believe its either of those two. In the early part of the year, Ford told me that I had a split "intercooler" pipe (or boost hose - cant remember, but believe it was the pipe) they haven't followed up on that. If someone could tell me where the blighter is, I could probably look to replace it myself (ford quoted £150 for the pleasure!).

Otherwise, I did replace the air filter, but didn't touch anything else (didn't really have the time amongst other things), Haynes are great at telling you what something is, but they are anything but helpful in showing you exactly where it is in relation to the rest of the engine bay, and the grainy photo's....

Most the hoses I can see, I have checked and all seem to be fine, I believe I had a split on my old MAF hose, which I replaced from the internet marketplace, but the smoke has reduced (compared to before the blanking) but its definately still there, and I dont fancy an MOT failure in November...

I think if you have a split in your boost/ "intercooler" hoses that is liable to be the cause of the exessive smoke - the injectors continue to inject the same amount of diesel, and the amount of air/ pressure entering the engine is reduced (due to the split/ leak in the hoses) - thats what causes the (boost leak induced) exessive smoke

There are hoses that tend to fail before others, certain ones may be under more pressure than others, there are ones that flex more (one end may be attached to the engine, the other to the chassis) on top of this, the oil/ oily spray entering the boost hoses from the breather can "melt" or break down rubber over time - the replacement silicone hoses are not so affected - so apart from being cheaper they are better too

Sometimes, when the variable vanes get coked up it can cause the actuator to stick/ or if there is a fault in the turbo boost control system and it produces too much boost - this can burst hoses - so worth checking that

Find out which is the common boost hose/s to fail, you could brobably pick one up for £20-40 and fit it yourself/ get a mate to do it

It would be worth cleaning out the inlet manifold while you are at it

well, I have looked it up and the intercooler pipe is a common one, I think I know which one it is (pipe between bonnet catch and engine) but I dont know for certain, I have emailed Ford and asked them to look at their records and see if they can confirm it is right and what the part is that I need to buy to replace it. I dont know how much of a pain it is to replace, but if I can do it myself I will, otherwise Ford wanted £150 to replace it, so if thats the line I must go down...