[wolfe99]

So having a bit of an issue.  have a 2018 cforce500ho.  Machine has ran flawless for 800miles.  Went to start it this morning and it wont fire up unless I hold the throttle open.  The EPS light comes on when you first turn the key on.  It will fire once it gets going .  But after it sits for a period of time same thing.  The EPS light is in when you turn the ignition on but will disappear when it finally fires up.  Any suggestions?

[doug80638]

I'm going to assume you mean the EFI light, and not the EPS light. Ignore the light unless it's blinking.

Did you recently fuel up?

Lots of things to consider. Check the plug gap, check the air filter (clogged?), etc...

What have you done for diagnostics so far?

[wolfe99]

No it is the EPS light but doesnt flash.  the problem did start when I put gas in it last so I added SeaFoam.  I run a Uni-Filter so I cleaned that and re-oil as well.  Once it finally gets going its ok.  But once it sits it goes right back to hard starting and have to hold the gas to start it .  Then runs choppy till I run it some

[doug80638]

If it's running well once warmed up than systems like injectors are working fine.

Check the simple stuff first.

I would question the quality of the fuel. Drain it or run it down low and refill with fresh, perhaps higher octane, gas and see if things improve. (We've seen this before)

I would also check the batter for CCA capacity and voltage as these systems get finicky with marginal batteries.

[paulp]

I'm going to follow your thread as my issue is a bit closer to yours, It starts but needs me to flex the thumb throttle once or twice to get it warmed up and the 2 i have are the 2020's.

[wolfe99]

Well changed out the gas with  91 non ethonal..  Started up did not want to start and when it did still choppy.  Ran it then idled fine ran fine.  Let it sit for a couple of hours same thing .. Have to feather the gas for it to fire up .  Then have to feather the throttle to keep it running then it seems to smooth out after a couple of min

[doug80638]

I would ordinarily read the ECU settings with a ECU interface program and check to see what the sensors are telling the ECU. For instance, an engine temp sensor that reads high will interfere with the ECU running rich for cold engines.

The ECUs in these are made by Bosch, and I haven't been able to find a good public source for communicating with these units. Only the dealerships seem to have these tools.

You can troubleshoot the sensors with a meter if you know the specs for the components, but that info isn't readily available either.

I'm an advocate for using the right tool for the job, so I would recommend bringing the machine to the dealer and asking them to hook it up and look over the sensor data. You might find out it needs a flash for colder weather (a known problem) or some other known conditions. You may have to pay for the diagnostic privilege, but at least you can get an accurate diagnosis to base a decision on.

Otherwise you can hunt around checking things like valve lash, clean intake and idle speed control, plug gap, compression when cold, those kinds of things.

Is it still under warranty?

[ctdls]

I've seen many bad NGK spark plugs cause start issue's with their V Twins. For the price of a spark plug try it.

[wolfe99]

Update :
  Took it to the dealer because its still under warranty, and what they found is the valves needed to be adjusted.  unit has 800 miles on it.  When I pick it up hope it has top end again !!