No faults.
Previously had the standard Focus Ghia 1.8 TD estate - ran for 45,000 miles with no problems other than casette jammed in stereo which was replaced under warranty (surprisingly). Have had Focus Ghia TDCi since March '03 and am well inpressed. Spec now includes full electric windows and single CD player (Ghia) and performance with the newer TDCi engine is much better. Economy suffers, but it's still better than the petrol equivalent. Handling is great fro an estate, but still missing basiscs from the standard spec like ABS! - unforgiveable on a modern car. Front screen de-frost makes up for it in the UK climate though.
I have completed about 20K miles in my Focus TDCi and am more or less satisfied with its performance and economy. It accommodates my frame perfectly and pulls well, but I'm not entirely sure that I'm satisfied with the fuel economy. If I drive extremely gently and do plenty of coasting where possible, I can just manage 50mpg - even on a run it never gets better than this. Quite how the manufacturer manages to claim a higher figure for the extra-urban cycle, I cannot say. I have experienced two faults on the car. Firstly, a flashing glowplug/engine-management light on start up which prevents the engine from firing. Some say this is an immobiliser fault, but that wouldn't explain why it is peculiar to the Focus and Mondeo TDCi's only. Other's say it is down to a faulty fuel pump sending shards of metal into the injectors which causes the engine to detect a fault. Ford recognises this issue and has a Technical Bulletin on it - they will also upgrade the fuel filter to stop the particles getting through. My advice to anyone experiencing this fault is to go immediately to their dealer for a diagnosis. Don't leave it too long because the engine's memory doesn't last that long and the fault code will disappear. The other fault is a failure to start despite the engine sounding like it wants to fire. It will only start when the throttle is depressed (which you should never do). Sometimes it shakes violently when trying to fire and the attempt must be aborted. Three trips to the dealer have so far failed to find or correct the problem and a fourth trip beckons. The trouble here is that the dealers rely on the on-board computer to tell them where the fault is. If this says nothing, they are completely lost. What worries me is the damage that could be building in the drive-train - and you can bet your boots this will only become fully apparent when the warranty has run out!
A good technician will use the diagnostic capabilities of the ECU as an aid, but most main dealer technicians now rely exclusively on them. To be honest, given a workshop manual, I could follow the instructions on a computer screen (change part X, adjust part Y). Technicians are supposed to have diagnostic skills to back this up.
I always remember my local Peugeot dealer taking ELEVEN attempts to diagnose some dirt in the idle stepper motor, which was causing my car to stall, and for the idle to set itself at 4,000 RPM whenever it felt like it. I was told on most of these occasions "the rig sez there's nuffink wrong wiv it. Sorry. Oh that'll be 60 quid plus VAT for an hours labour."
My current Focus TDCi has recently developed some of the symptoms you describe, and my heart has well and truly sunk. Bring back points, carburettors and old school mechanics!!