2016 KTM 250xcf-w. EFI stopped enriching "chokeing" fuel for cold start

Very hard to start when cold, no fuel enrichment.  Have to pump throttle and run at high idle for 30 seconds. Starts normal when warm. Anyone else have this happen and knows how to fix it?

Edited by chainsaw036

1. pumping the throttle does nothing

2. there is no enrichment; it's just a fast idle knob

3. Do a passive ecu reset (should do it before each ride)

4. Valve clearances ?

I know it doesn't have a pump fuel squirt-er on the throttle but rolling it up and down does help, otherwise it dies. Forget the idle knob, the fuel injection control is supposed to feed rich mixture for cold startup. What is an ecu reset please. Valve clearance are spec, recent check. Thank you for your reply. Bike starts easy when warm and runs strong, actually it is a great bike. Over 100 hrs on bike.

There is no 'auto enrichment' on your FI system. The ecu only makes correction upon start up between 170 and 220 degrees . At no other time is fueling altered by the ecu. Turn up your idle 4-6 clicks and start the bike using no thrortle. Let it idle with no throttle till it starts to percolate coolant (10 min). Shut off, restart and correct the idle speed. 

If you are unable to do this, you have an issue:

Dirty TB sensors

Dirty/clogged fuel pump filter. Replace it.

Compromised fuel pump from running a clogged filter. Test and replace

Corroded injector nozzle from not filtering or treating your fuel. Pressure clean per you tube videos

All of this is in your oem service manual

Fixed. Only read the instructions if all else fails. Problem was sudden cooler weather. Supposed to pull out idle knob below 68 degrees, did that and it starts immediately and holds high idle till push knob back in.

Thank you very much Team TT for your information and helping me.  As far as 'auto enrichment', I assumed that being EFI it would be smart enough to enrich for cold temp but I was wrong on that. Have never dealt with EFI before this bike. This 250 xcf-w pulls so hard at low rpm that it is hard to believe a 250 can do that. Never flamed out in a hard 2-3gear lugging pull in over 100 hrs. Of course I'v killed it and stalled it being a little sloppy maneuvering around and such.  I hope pulling the knob out is the only thing and no other problem is actually working its way into all the sensors.

thanks again


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