High idle

5 replies to this topic
  • MJScore

Posted April 20, 2006 - 06:11 AM


Buddy's got a 2002 426. Was running great but now when we go on a ride the idle rises. He adjusts it down but it keeps on going up. Fooled around with the air screw but still does the same thing. He taken the carb apart and cleaned out the jets so we don't think that it is a dirty jet. He has the PowerNow and Boysen cover. Jetting per the instructions. Like I said it was running fine until the last two rides. any suggestions?

  • jamieyz426f01

Posted April 20, 2006 - 06:15 AM


check for an air-leak in the rubber boots, could be sucking in extra air thats causing the higher idling :thumbsup:

  • viking_in_wa

Posted April 20, 2006 - 06:59 AM


is this a HANGING idle that eventually comes down on its own ,or stays reved up a bit?

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  • MJScore

Posted April 20, 2006 - 09:34 AM


It just idles high when you come to a stop. Does not idle down until you adjust the idle screw. I will check the rubber boots.

  • battles2a5

Posted October 31, 2006 - 12:58 PM


I'm having the same issues. Keep up posted!

  • WFOracer

Posted October 31, 2006 - 02:46 PM


This is a lean condition....which could be an air leak. Make sure that you do not have any additional air entering the carb (ex. cracked air boot, no air filter, no seat....)

Since the temps are cooler this time of year the air is denser. More air, means that you need more fuel. I would go up a size on the pilot jet and possibly a size on the main.

Here is a link to Eddie's (aka Burned's) method for check the pilot circuit.

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