2004 Skidoo Tundra Skandic Series Service Manual, Page 97Get this manual

Section 03 TROUBLESHOOTING Subsection 05 (ELECTRICAL SYSTEM)
SYMPTOM CONDITION TestInspection

FOULED (BLACK) SPARK PLUG TIPNORMAL USE1Check carburetor(s)aCarburetion is too richAdjust according to specifications (refer to TECHNICAL DATA)2Check injection oil consumptionaInjection pump flow is too highAdjust according to specifications or replace3Check oil qualityaPoor quality oilUse BOMBARDIER injection oil4Check engine compressionaLeaking piston ring(s)Replace
SYMPTOM CONDITION TestInspection

• ATV
• Jet Ski
• Outboard Motors
• Personal Watercraft
• Snowmobiles
• Stern Drives