That isn't easy to diagnose in a forum.

An OBD scanner isn't the best tool to use as they are generic scanners.

You need to get your motor scanned (preferably with VAG-COM\VCDS) for any error codes logged in the ecu and post them, that will save a lot of guessing and check systems out.

What record have you got when the fuel filter was last changed? They should be done every 20,000 miles.

 

It can be the injectors on the BXE engine, I get my customers to run them on V Power and see what happens. Yes you MUST replace the rocker arm and injector bolts, it is VITAL, a snapped injector bolt will ruin your day... well week or more! Fitting a set of exchange injectors from Bosch, all the others are rubbish and Euro car Parts want £1500 EACH for them PLUS £132 surcharge which is more than double the VW main dealer retail at £647.40 each, they even want £515just for the "Lucas" branded ones but bear in mind this is NOTHING to do with the Lucas of old, the name is licenced to Standard Motor Products just down the road from me in Hucknall and they used to go under the name "Intermotor", a brand that strikes fear into the heart of any old soak mechanic. You can get Bosch ont tinterweb for £500 each but remember the surcharge and return shipping, probably to Germany. New injectors MUST be installed with new ball pins and tappets, and the stoke accurately set. The seal kits with the ball pins are 038 198 051 C and cost £37.52 genuine per injector, new injectors come with the seals. You can get full seal and pin sets from many companies such as Febi for around £12 per set. Often when removing 8V PD injectors you find the bores are damaged and even new injectors can start to leak after installation with new seals and that means a new head so usually we take out the injectors, see the damage and scrap the car for the owner.



One fun one that has happened a few times to us is an injector that is stuck, using the special VW slide hammer you can get them out but they leave the end of the body stuck in the head which is great fun...

 

I get my customers to run them on V Power and see what happens.

Are you suggesting running on V power permanently or for duration of fault to determine symptoms.
The car still has a miss and i'm on to my 2 tank of V power, however the car is smoother & quieter.
Given that the economy is still good, its possibly worth running on V power full time.
I have yet to have the ECU codes read but hope by this time next week, it will be done.
Thanks to all who have offered advice and input so far.[/COLOR]

 

Permanently use V Power. IF it is going to help it will take time, try running some powerful diesel cleaner as well, this is good stuff https://www.ebay.co.uk/itm/Red-Line...e-85-Plus-Diesel-Fuel-Additive-Treatment-12oz-/370897304055?hash=item565b33b9f7 and has sorted out many minor issues for my customers.