On/Off severe misfire due to one bad sparkplug on my 998.

[Rydernow]

I never in a million years would have been able to diagnose this misfire as a bad plug. It would on and off again act like it was just putting along on one cylinder then accelerate like a rocket ship. I could barely control the ride while trying to deliver it for diagnosis and repair. I figured it had to be a coil or injector trying to fail. Just a bad plug. Have any of you had this happen to your 998?

[Freddy]

Not a bad plug but lots of bad plug leads.

[Rydernow]

I bet you're right. I tried pulling em off prior to taking it in but they seemed so stuck on that I figgered i'd tear em up.

[sledge]

It's really hard to find a problem that just comes and goes. I worked as a mechanic most of my life, anything electrical, (Coil, Coil Wire, Power to the Coil, or a Spark Plug) that works sometimes and not at other times is a royal pain. Always start with the smallest, cheapest, and easiest to find Part.

[EDBLU]

I never in a million years would have been able to diagnose this misfire as a bad plug. It would on and off again act like it was just putting along on one cylinder then accelerate like a rocket ship. I could barely control the ride while trying to deliver it for diagnosis and repair. I figured it had to be a coil or injector trying to fail. Just a bad plug. Have any of you had this happen to your 998?

Yup on a '13 and '15

[BLUEKNIGHT911]

I never in a million years would have been able to diagnose this misfire as a bad plug. It would on and off again act like it was just putting along on one cylinder then accelerate like a rocket ship. I could barely control the ride while trying to deliver it for diagnosis and repair. I figured it had to be a coil or injector trying to fail. Just a bad plug. Have any of you had this happen to your 998?

It took me awhile to find out WHAT ..998 you were referring to ( it matters ) .... You have mentioned an 08 GS in your posts .... if that is the year and it still has the orig. plug wires , then you have been very very lucky it/they lasted this long ... Can-Am's are notoriuos for plug wire failure ..... I think FREDDY is spot on ..... Mike