96 xp 787 intermittent or sporadic spark off idle

[Jim G.]

The spark becomes intermittent or sporadic when you push throttle or off idle: at idle it is OK: So far I have put on new plug wires, plug caps, spark plugs, rectifier and pulled stator cover and checked the pickup: the pickup has 240 ohms and is not broken and the coil ohms out good: IS there anything else to check for besides the mpem? Is there any way to check the mpem: My book gives some ohm readings to take but I have been told that is not true: Please help: Thank You

 

[timmyboy76]

mpem test...

1995 XP 800 & 1996 XP GSX Models
( 278-000-858 DC-CDI Test )
Meter (+) Lead Meter (-) Lead Value
Red/Purple Black 2.6 k ohm
Yellow/White Black 0.380 M ohm
White Black 2.208 M ohm
Black/Orange Black infinity
Black/Grey Black infinity
Black Black 0.2 ohm
White/Black Black 30.38 k ohm
Black Red/Purple 2.690 k ohm
Black Yellow/White 0.390 M ohm
Black White 2.2 M ohm
Black Black/Orange infinity
Black Black/Grey infinity
Black Black 2.69 k ohm
Black Grey/White 33.07 k ohm

also you can Unplug the black/red wire between the mpem and coil and see if it starts. If it does, you have an issue with a switch or the rev limiter in the mpem. If it doesn't, the stator or coil are the places to look. Also, if it does start with that unplugged, be prepared to kill with the choke since the stop and lanyard buttons are bypassed
Or, disconnect the red wire from rectifier, see if that cures it,..you stated that you purchased one, but never know...:cheers:

 

[Jim G.]

I did Unhook the red wire from the rectifier before and it would rev up real good but then totally die until I unhooked the lanyard and plugged it back in. I thought it was the rectifier so I bought one on ebay but it still did the same thing: So I had doubts about the one I bought on ebay so I bought a new one and put it in and it still doing the same thing: I will do the ohm test on the mpem today and I will let you know what I get:
Thank you

 

[Jim G.]

Ohm test results:

test lead + - respectively

red/ purple black 3.44 k
yellow/white black .34 k
white black 2.14 k
black orange/black = infinity
black grey/black = infinity
black black .1
white/blue black 29.8 k
black red/purple 3.44 k
black yellow/white .35 m
black white = infinity
black black/orange = infinity
black black/grey = infinity
black red/purple 3.44 k
black grey/white 37.6 k

I will have to put engine cover and everything else back together before I can do those run test:

Thank YOU