Your looking for a smooth trace rising with RPM,

You do not want to see dips/bumps or big fluctuations.and a faulty FPS will show up in live data read.

Of course if you do see fluctuations then it's on to testing why.

Which could be a number of things.

Any diesel that cuts dead my first suspect is the crank angle sensor which will never show up as a code on an ebay reader

,the ecu just sees it as you've turned the key off!

Depends on how good the tech is.

£100 is my start price for this,

and I'll throw every test I have until the fault cause is narrowed down.

problems happen when I hit a point where cash has to be spent before testing can continue.

Say a faulty injector,no gntee that'll fix the fault but without fitting one I can not continue with testing.

This is where it can get complicated.

A good tech will be able to narrow the area of the fault only so far,

if your unlucky that is.

Your right buddy, similar problem to my newly purchased 08 1.4 TDCI, local garage couldn't read the code so took the car to my local Ford dealer, cost me nigh on £250 and still no answers. I took the car there to get quick answers because they have the proper kit right ? how wrong was I. As is the way loads of people are now telling me (after I've bought the thing!) that the 1.4 TDCI isn't a very good engine and they have lots of history with issues like this, (you'll be luckey to see 100000 miles out of it, was one comment) one guy told me he even scrapped his car due to mounting 'Tech' bills!!. How can a so called 'Tech' (as they call themselves these days) justify charging so much money and getting no where??? even you yourself say you start at £100??. It's very frustrating when there is all the modern equipment around, plug and play etc and you guys are still none the wiser than some old boy in a back street garage!....very very costly to jo public and very profitable to Ford dealer everywhere., I guess at the end of the day you can't beat a good old 'mechanic'.

Please let me throw this in as a reply! :

This thread is from January 2014, and since my reply at that time, my own 1.4TDCi has suffered this problem. It started with a noisy injector. The injectors first had new seats and seals after its second MOT (2011) when the 'foot to the floor' emission test blew out a seal, and late in 2014 the injectors were noisy again. I took it to a 'recommended' local garage. It came back still noisy as before, and this time losing power intermittently, but only until it fully warmed up. There was simply no point in doing diagnostic checks.. It needed stripping down again to find out what the chap had done - or not done! I took the car to the local diesel specialist this time. They spent all day on it, replaced seats and seals and said they had to re-cut one seat because 'it had a screwdriver cut in it'. They say they replaced the leak-off pipes as well. It's run well ever since and it's now done 198,000 miles.

My conclusion is that this engine does suffer from failed injector seats, seals and leaking pipes. Forget diagnostics - just let a proper diesel specialist strip it down and sort it!