Mk1 Ford Focus Misfire and struggle starting

[jasonrb]

Hi all, I'm new here so go easy!

I have a Mk1 Focus 1.8TDC on a 54 plate.  Recently breezed its MOT but was very 'carboned up'. My mechanic added an additive to clear it and all was well.  Then another mechanic told me I need to thack the car occasionally to clear it out which I did.  I drove the car later on after doing this and at idle the engine was misfiring.  Replaced the injectors and this seemed to sort it out.  Got home yesterday, pulled into my driveway and switched off the heater and the front and rear demisters and the engine was misfiring again??!! Switched the engine off and left it a few secs and fired it back up and it idled fine?? Any ideas?

Problem 2, if I start the car and drive it round the corner or to work which is 2 miles away, when I start the car up 8 hours later at work it really struggles to fire up?? I broke down some months back where it just wouldn't start and apparently there was air in the system?? Any help or advice greatly received.

I drove the car on a 400 mile round trip a few weeks back and it drove absolutely fine so I'm hoping it's nothing to sinister to sort.

Thankyou

[williamweb]

Ok buddy,how much to change your injectors?If you are only traveling 4 miles a day and the odd trip I would question owning a diesel.Change the fuel filter and air filter.

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