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2004 Honda 400ex Misfire

JimB

By JimB
in Honda ATV Forum

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JimB Newbie

JimB

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Hi Im new to the site , I have a 2004 Honde 400ex it starts and runs strong down the road but when idleing it acts like it is misfireing or un burned gas is building up and the fireing.

I have taken the carb apart clean all ports new dyno jet, jet kit with a 170 and no air box lid just like the instructions clean k&n with outerwears new spark plug , fresh 100 octane fuel. Any and all sugestions would be appreciated.

louk Newbie

louk

Posted
Posted

sounds to me like your low speed idle jet is clogged if it was sitting for a while boil some water with lemon juice and put your jets in it for like 5 to 10 minutes should open them up

Louk

  • 10 months later...
JimB Newbie

JimB

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I have tried everything, today i remove the decompression and with no avail , it still has this miss almost like it wants to die for a few rpm and then back to life for a few and then again back and forth , but when you run it down the road the quad runs like nothing wrong at all

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