2003 1.2 vw polo hard question. I`ve just done the clutch and it has`nt run since. Spark plugs getting?

soaked but there is a spark. Borrowed a technician and his diagnostic equipment," I,d already checked and rechecked all wiring and plugs that were disturbed", he said it was the main multifunctional relay, first and cheapest option. Second being the ecu. Changed the relay,no result! Sent the ecu away for testing and that too was ok, Phew! But car still wont start. HELP and save some of my hair.