I have two 2000 TBlazers and I have been having a bogging problem with one of them. The other works fine and I've checked both plugs and they look the same good choc. brownish color. I use the polaris gold oil in both. This happens when first ridden or after it's well warmed up.

The bogging happens when you first push on the throttle then goes away and runs fine until you get to full throttle then it bogs again. This gets to be a real hazard when trying to climb hills and you need that extra throttle, instead of a push of power when you need it you slow down instead!

What could be causing this? Being the plug looks fine I'm really baffled. Anyone else had this happen

 

How old is the gas? That's the first thing I would think of.

After that I wonder about the rings since it seems to have spark.

What do the rest of you think? Is there any easy way to check the rings without tearing it down?

 

Try moving the clip up on the neddle in the carb. Moving clip up drops needle giving less gas.
Should be on the middle position from Factory. I moved mine to the top position and the throttle reponse increased noticeably.
99-TB K&N DG Pipe
99-Sport K&N

 

FYI

I called the dealer's service guy and he said first check the intake manifold bolts and air cleaner boot clamp to see if they're loose and letting air in. If not then clean out the carb, since I had stored it for several months without putting stabilizer in the tank (old gas could have gunked up the carb as 00TB250 suggested).

As far as dropping the needle (leaning out) would that not be bad since it's not fouling right now? Maybe a hotter plug would be good if the other remedies do not work. Do you other TB owners use a B9ES or B8ES NGK ? (I think with NGK the lower # is hotter)

 

My 1996 trailblazer did the same thing. The dealer installed a new neddle and seat on the carb. The problem was is at low rpm, when you punch the gas a large dose a gas floods the carb. This causes a "bog" but then comes back to life. Being that your machine is new, the needle and seat should not be worn enough to cause a problem one would like to think. Sounds like it is just plain running rich. Try the hotter plug.

 

I'd say it's your boot, could be cracked

 

Well to follow up I thought I would post my remidy to this.

After checking the boots (no cracks and both were tight) I looked in the air box. There was a slight crack just to the right of the intake where a rubber bumper slides onto a plastic post (on the outside of the box) which rests on the tranny. From a previous post I think it was fastrnu that said he gooped then trimmed the post and rubber bumper, I did the same.

This was not the problem, still gasped at throttle beginning and end.

Took dealers advice and took jet needle off to clean. Sure enough the tip if the jet needle was gummed. Cleaned it and now the gasping was at full throttle only.

Took entire carb off and cleaned main jet and every orifice I could spray with carb cleaner. I noticed alot of gumm deposit at the bowl bottom and inside nut to access main jet.

Problem solved! It was just dirty jets.

Lesson learned: Always use stabilizer when storing and use regularly to keep carbs clean!