Wel bro i hav vitz 2004 too wid italian cng landi ranzo kit installed in it! same thing hapenz wime too, i gt chkd it by ma mechanic via obd2 port car computer, it gav a code dt defined FUEL TRIM! actually uzin cng cut petrol outa petrol pipe so itz sensor blinkz da check lyt! it iz abs ok, dnt wory n enjoy ya ryd!