Help! m52 not running :(

[VW-will]

hi guys, i done my m52 conversion coming up 2 years ago now, its been in 3 cars since then with no issues, recently the cars been off the road and the battery went flat, since then the car will not start, list of parts ive tried - ECU - (Ews removed remapped etcetc) New crank position sensor new cam position sensor, ive also made a new engine loom (has made the matter worce, than before if anything, (think i recieved a loom that isnt compatable) i have fuel (injectors are working) just no spark, its really starting to piss mee off now, lol! im at a lose end of what to try next, tomorrow im going to go through the old loom (the better of the 2) repair where needed and re-fit see if i have any luck that way, anyone expieriance the same? if so what did you do! lol thanks very much Will

[slim91]

Sounds simply but have you tried putting a heavy earth strap on? Mine would turn over a work perfect but no spark still my cause was a weak earth.