hi people ive got a 52 plate astra van 1.7dti that is running very bad.its running very slow most of the time but now and then throught its drive will return to normal power,then back to really so and so on constantly changing.first thing in the morning fronm cold its like a rocket then with in minute of driving back to slow and really slow under 2000rpm.also when its running slow theres loads black smoke out the back when on power.
so far ive had it on snap on machine no faults other than brake swich malfunction ive changed this and cleared faults and now its saying no fault anywhere but still ruuning crap.please please please help desperate to get it running good feels like got no acceleration at all just flat and now then it will work ok keeps switching every 5 seconds or so through out every drive,but weird thing is in first thing in the morning its a rocket for a minute then thats it for the hole day back to slow.please help