2003 Ski-Doo ZX Series Factory Shop Manual, Page 77Get this manual
Section 03 TROUBLESHOOTING Subsection 03 (FUEL AND OIL SYSTEMS)
FUEL AND OIL SYSTEMS
SYMPTOM CONDITION TESTINSPECTION HIGH FUEL CONSUMPTION OR RICH MIXTURENORMAL USE1Check fuel tankaPerforated fuel tankReplace fuel tank2Check fuel pump, reservoir and carburetor fittingsaLeaking fittingsReplace defective part3Check choke adjustmentaFuel flows through choke circuit while engine runsReadjust choke4Check float height in carburetor(s)aFuel level is too high in float bowl(s)Adjust according to specifications (refer to TECHNICAL DATA)5Check needle valve on each carburetor