'99 ZL 600 EFI Bogs out and backfires - Snowmobile Forum: Your #1 Snowmobile Forum

scottr · 01-31-2006, 11:38 AM

I need some help. I just bought a '99 ZL 600 with 3100 miles on it. I had it out on Saturday and ocassionaly it would fall on it's face when I hit the throttle. This would mainly happen after cruising between 30 and 40 mph and on uphill slopes. I'd hit the throttle and it would bog out. Hit it again and it would take off like you'd expect. Sometimes it would backfire through the exhaust and then take off. I changed plugs on the trail and it didn't effect the way it ran. It finally died about a mile from the cabin just after crossing the highway. I pulled the plugs again and they looked fine, had spark at both plugs, put the plugs back in and it fired right up. I don't know if I'm dealing with bad fuel or maybe something electrical thats heating up and cutting out. I tried taking it out on Sunday and it started doing the same thing immediately. Any help would be greatly appreciated.

**RJ Gleason** · 01-31-2006, 11:42 AM

Have you got old gas in it? There may be some moisture in the tank.

You can put some dry gas in and also use a little injector cleaner to see if that solves the problem.

scottr · 01-31-2006, 12:03 PM

It had about a 1/4 tank when I got it. I don't know how old the fuel was. I filled it before heading out. I'll try some injector cleaner and replace the fuel fillter. Should I drain all the old fuel from the tank and if so, is there an easy way to do it?

**RJ Gleason** · 01-31-2006, 12:20 PM

Siphon hose works best to drain the tank.

letitsnow · 01-31-2006, 02:29 PM

throttle saftey switch.

lovethepowder · 01-31-2006, 03:41 PM

My jag was doing the exact same thing yours was doing a little while ago. It doesnt sound like you have the same problem but the problem for me was that a fuel line was cracked so the engine wasnt getting enough fuel.

scottr · 02-14-2006, 09:55 AM

Thanks for your help. It was the throttle safety switch. I drained the fuel tank and filled it with new gas and 1/2 bottle of injector cleaner, then ran it about 10 miles. It was still bogging and backfiring. I unplugged the T.S.S. and it ran fine the rest of the day.