Artic cat 400 starts when it wants to, i susspect the choke

check carb may need cleaning rebuild or replacement also check primer unit for possible failure

Probably needs a carburetor rebuild.

Has the control system been scanned for fault codes? Do that first.

Sometimes when bad parts heat up they fail. I have seen this with the cdi. Be very aggressive when checking your connections. Do you lose spark after it has been run for a while or at certain temps?

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Does your artic cat have a carb cable if so it will have an adjustment or a clamp on the cable where it attaches to the linkage..check make sure it is set to low idle..and your idle screw is adjusted to low idke..meaning cable adjusted to lowest possible position when the throttle is released..then make your final adjustment using you idle screw..good luck

From what I understand it is stamped on the left side of the cylinder head, behind a hose.

If this does not help, contact artic cat dealer and speak to a service rep.
Hope this helps!

guessing you changed the spark plug? .. you can fry the coil from heat...I used to wrap coils in rags when I tested them on a coil tester to try to make them break down from the heat quicker. It worked too.

I had this problem with Artic Cat 500 and after ensuring the electric shift was working I discovered the mounts for the front drive shaft had broken and would not allow the shaft to engage. I suspect mine was caused by plowing but any number of things could break or bend these.

my artic cat did this found that the carb was dirty