will not rev over fueling prob mk 2 1.8 8v digifant

[llp golf]

this problem started a couple of days ago to get it started you have to disconect yhe power plus from ther injector rale then turn the key it fires up for 2 seconds to burn off the fuel in the engine then you plug it back in then you acn just get it to idle well below 1000rpm then when it has been ticking over for about 10 mins you can feather the throttle and get it to rev but it chucks out black smoke and pops and bangs then if you put your foot to the floor from idle the revs downt pick up it just gose bh bh bh bh bh its like the injectors are putting to much fuel in the cyilnders then you switch it off then it will not start agen help needed asap

[rubjonny]

this is caused by a dead ECU, usually becasue its been blown due to a bad gearbox earth.  The first thing to do on any digifant is remove all the battery, starter & alternator wires and clean them up with sandpapaer till they are proper shiny, then refit.

[llp golf]

well i have changed the ecu and air flow i done a compression test to but thats fine my mate is having a look now and he seems to think the cam belt has jumped so we will see