Few months back my 1uzfe conversion suddenly did not start. Was perfectly fine a few hours before. I cranks like normal, wont start and very strong fuel smell. Had it towed to my mechanic, he cant seem to find any problem with it except the sparks get really wet with fuel once key in ON position hence it wont start. Says he can see fuel leaking into my exhaust system. He claims its an issue with the ECU/wiring/sensors (mech doesnt know much about electronics). I havent have time to drop by to run the diagnostic. Anyone has experienced this before?