Stihl ms400c stalling

[junglejohnny28]

Have a 400c that’s starts snd runs but then shutts off .if u go to reset computer sfter 60 seconds of idle u hit throttle revs for about 20 seconds snd shuts down .anybody have this happen and any points on fixing

 

[chipper1]

@farmer steve any ideas.
Dang stihls .
I still gotta try one of these 400s sometime.

 

[huskihl]

The calibration procedure is 30–60 seconds in the start position, and then hold the throttle wide-open while it goes through its series of adjustments. Maybe not going wide open until after 60 seconds is causing it to act up? Not certain but maybe.
Try it at 45 seconds instead and see if it will calibrate..

If it still won’t calibrate, I would replace the fuel filter and spark plug and I would try cleaning the carburetor.

 

[SAWMIKAZE]

Have a 400c that’s starts snd runs but then shutts off .if u go to reset computer sfter 60 seconds of idle u hit throttle revs for about 20 seconds snd shuts down .anybody have this happen and any points on fixing

Are you doing that 60 seconds with the chain brake on like you're supposed to ?

 

[stihltech]

Yep, must be the Mtronic. Look past the "OH MY GOD IT HAS A COMPUTER!", and treat it like any saw with a carburetor to diagnose.
I would start with the fuel system. Fuel, filter, hose, screen inside carburetor, condition of carb body and diaphragms.
Did the pulse hose pull off?

 

[junglejohnny28]

The calibration procedure is 30–60 seconds in the start position, and then hold the throttle wide-open while it goes through its series of adjustments. Maybe not going wide open until after 60 seconds is causing it to act up? Not certain but maybe.
Try it at 45 seconds instead and see if it will calibrate..

If it still won’t calibrate, I would replace the fuel filter and spark plug and I would try cleaning the carburetor.

It would not reset all the way threw sequence it ran for a min held wide open after 10-15 seconds shut down . Replaced the m tropic solenoid and was the problem ,Ty