My Yager is stalling!! Please help

[JJJoseph]

If it was the coil, it would show on the diagnostics tool.  Isn't there someone in this audience who knows how to use the Kymco diagnostics?  Someone hinted at using the diagnostics, but no detail followed. It's painful watching all the wasted guess-work going on here!

[CROSSBOLT]

So sorry, JJ, no code for malfunction in coil. At least on the DT code roster which is SIMILAR to the Yager. Someone with the Yager service manual could close that loop. DE DEE! WAKE UP! Codes for Yager, please! US calling Canada, over.

[Stig / Major Tom]

So sorry, JJ, no code for malfunction in coil. At least on the DT code roster which is SIMILAR to the Yager. Someone with the Yager service manual could close that loop. DE DEE! WAKE UP! Codes for Yager, please! US calling Canada, over.

You want the number for Timmies up there, Karl?
(got 'em all on speed dial)

Stig

[CROSSBOLT]

Who "Timmies?"

[Stig / Major Tom]

Who "Timmies?"

Canada's second most famous personage, after the RCMP's, Tim Horton.
Dedee is probably hanging out there.
Stig
Stig

[de dee]

 no timmiys for me I have home cooking yum yum   bringing tool to jim soon , but I am not good on diagnostics,.   Ill bring my yager and cross check from one to the other to see if there is a difference,.   

[Louder North]

no timmiys for me I have home cooking yum yum   bringing tool to jim soon , but I am not good on diagnostics,.   Ill bring my yager and cross check from one to the other to see if there is a difference,.

Thanks De Dee!  I've got your diagnostic tool and realized that if I leave it under the seat, I can't see it unless I turn off the ignition (which then powers off the tool and you lose any DTC it might have detected...). 

So, the cable is long enough that I could route it under the seat and leave the tool in my pocket; so I did another tour of the neighbourhood, again repeating the 'moderate speed stall' symptom, got home, checked the tool with the engine still running...  and there were NO DTCs!  No trouble codes.  All is within spec.  So now I'm thinking 'what else can it be'? Could it be fuel related and therefore not detected by the diagnostic tool? 

Took the floor board off, measured the resistance of the fuel pump...  it is supposed to be 1 ohm (+\- 0.2 according to the service manual).  It measures 2.7 ohms.  Yes, it is out of spec and I would say while it still pumps, it is too weak, and therefore not able to supply sufficient fuel pressure when under load.   Time for a new fuel pump!  \

I took the pump right out of the fuel tank and have some pictures of the filter - let me know if you think it might also be plugged up. 

[Louder North]

So sorry, JJ, no code for malfunction in coil. At least on the DT code roster which is SIMILAR to the Yager. Someone with the Yager service manual could close that loop. DE DEE! WAKE UP! Codes for Yager, please! US calling Canada, over.

I can confirm there is no DTC for the coil.  It displays idle RPM, battery voltage, TPS volts at idle, TPS volts at WOT, atmospheric and manifold pressure in kPa, fuel injector interval (in ms), ignition advance (in degrees), ABV angle (in degrees), sensor voltage (in mv) (I think this refers to O2 sensor), O2 heater (on or off), ABV adaptation (in degrees), ECU counter (total hours of operation), cutout voltage, ignition dwell (in ms) and air temp.  For DTC it will display current, previous and history of DTC codes. 

[de dee]

remember  yager 200  he had stalling too,.  he installed new filter from auto supply and same problem  he ordered a  micron fine filter and that solved the missing  if we look up his measages,  we could see where he ordered it.,  and how fine of a filter,

[Louder North]

remember  yager 200  he had stalling too,.  he installed new filter from auto supply and same problem  he ordered a  micron fine filter and that solved the missing  if we look up his measages,  we could see where he ordered it.,  and how fine of a filter,

This is the thread you meant right de dee?  http://www.kymcoforum.com/index.php?topic=12666.0

[Louder North]

Thanks De Dee!  I've got your diagnostic tool and realized that if I leave it under the seat, I can't see it unless I turn off the ignition (which then powers off the tool and you lose any DTC it might have detected...). 

So, the cable is long enough that I could route it under the seat and leave the tool in my pocket; so I did another tour of the neighbourhood, again repeating the 'moderate speed stall' symptom, got home, checked the tool with the engine still running...  and there were NO DTCs!  No trouble codes.  All is within spec.  So now I'm thinking 'what else can it be'? Could it be fuel related and therefore not detected by the diagnostic tool? 

Took the floor board off, measured the resistance of the fuel pump...  it is supposed to be 1 ohm (+\- 0.2 according to the service manual).  It measures 2.7 ohms.  Yes, it is out of spec and I would say while it still pumps, it is too weak, and therefore not able to supply sufficient fuel pressure when under load.   Time for a new fuel pump!  \

I took the pump right out of the fuel tank and have some pictures of the filter - let me know if you think it might also be plugged up.

While still waiting for the fuel pump from Solano for my gray Frost, another Frost came up for sale in my area.  Pristine condition, newer year, fewer kilometers, white in colour; the price was right so I bought it.  Will still repair my first one but will sell it next year (I still have your diagnostic tool de dee!).

[Louder North]

Well, after consider efforts to no avail on my part, I am happy (but also a bit chastened to confess) that I have, finally, sorted out the cause of the moderate/higher speed stalling and tachometer 'diving' issue.     

Faulty spark plug cable.  Photo of culprit attached.

My fault for starting at the coil and working the other way to the stator.  Then thought is was a fuel issue.  Fuel pump checked out, no plugged air vent from the tank, fuel vapour value OK too. I taped the outside of the sparkplug cable also to ensure no leakage, as was reported in this thread but that didn't help. On the plus side, I have learned a lot about the electrical and fuel system but the most important lesson for me was that I should have started on the easy to test/fix items first. 

[Louder North]

With the help of the parts counter guy at our local MC store (Ottawa Good Time Centre), I salvaged the connectors on the old spark plug cable and added them to a new $1 piece of cable. 

Runs like a charm now.

[CROSSBOLT]

One buck for a piece of spark plug cable and it is smooth as glass! That fuel filter looked pretty grubby! You now the Yager/Frost expert! Good persistance!