low voltage

[buzzcut]

Hi all.  Running into an oddball problem and I don't know where to look next.  I am getting 12 V at the coil on plug mod at idle up to 2000 at which point it drops to 2 volts on both sides then after 2000 rpm it is back up to 12 v and runs really nice.  Anyone encounter this and what am I missing please (besides spark) 

[T Cro ®]

Strengthen your ground (Black wire with Yellow stripe) in several places; namely close to the igniter under the seat. Check your switches that pass the (+) to the Red wire going to your coils; could be vibration induced drop due to dirty switches. 

[buzzcut]

Thanks Tony,  checking.  I'm the one who PM'd you on the wiring diagrams a couple days ago.  I'll let you know what comes of it.

[T Cro ®]

Thanks Tony,  checking.  I'm the one who PM'd you on the wiring diagrams a couple days ago.  I'll let you know what comes of it.

Not enough coffee for me to catch/match names....

[buzzcut]

follow up..pulse coil voltage is steady through the 2000 rpm hiccup.  Input voltage to the ecm is steady, only the output voltage from the ecm varies in concert with the hiccup so I have ordered up a used cdi box.