spark issue with rb25det

[morton]

hey, i have a rb25det in a nissan patrol and cant get any spark on 2 cylinders, the vehicle has no signal to the coils, ecu igniter coils and coil harnes has been replaced have got knock sensor signals at the ecu but cant pinpoint were the issue is

[Joe]

lets start with some basics

move the coils to 2 other cylinders, move the spark plugs to the 2 other cylinders left

report what happens.

[morton]

cheers, have done that there is no signal from the igniter to the coil as there is on the coils, i also seem to be getting a 12v signal out of the ecu unlike the out puts where there is a nice wave form signal pattern

[240z4u]

Sounds like either a chafed wire, bad ground, or possibly bad CAS. Are the injectors all firing?

Evan