This one really had us scratching our heads for a while. One of our Ski-Doo 800s fitted with the PowerTEK engine package had a problem at the end of the year where the muffler would get really (and we mean REALLY) hot, so hot things started to melt. It would run good at about half throttle and above, but had difficulty idling. The check engine light came on and started flashing.
We first suspected the sled had gone into a timing retard mode, which built pipe heat, and after some steady running the heat got to the point that we could smell things getting hot. But, this wasn’t the case.
Instead, our Ski-Doo technicians discovered cracked carb intake boots, thus an air leak and a resulting lean condition. The sled was trying to compensate as much as it could, and did a great job, but the continued operation in this state led to the muffler getting extremely hot.
So, this episode reminded us of the importance of paying attention to your sled’s operation and maintenance. If you notice a sled running unusually hot and lean, the rubber carb intake boots have been known to crack on occasion. In this case it wasn’t a case of rot or deterioration as much as it was 3,000+ miles of cross-country pounding and a dose of bad luck. This particular sled was a 2006 MX Z 800 PTEK.