Vs Series 3 Ute possible ignition issue diagnosis

[IzPr0J]

Thought I'd get a second opinion on here, recently aquired a vs ute it came with a raptor supercharger. The supercharger broke so I'm in the process of converting it back to Naturally aspirated, I have done the following:

Installed stock idler pulley
Installed belt
Installed intake tube air box
Put the PCV hose back on throttle body
Taken off the unnecessary join and extra hose on the heater control hose that went to the blow off valve
Changed the ECU to a stock vs V6 auto one
Taken of the 85mm plugs and put regular ones on

Since then the car runs poorly, like it's running on 4 cylinders... I've gone and taken of 1 by one each plug lead and cranked it over and it runs the same every time, I've also tried unhooking hoses to no avail. Would I be right in thinking it might have something to do with the ignition? Or would it be something else. I'd might add there is an engine light that pops up, so would it be worth it to invent in a scan tool and witch one? Please forgive me as I am fairly new to tinkering with cars, this is also my first Holden after owning 2 Fairlanes so it is an adjustment. If someone would be kind enough to help me pinpoint what my issue is, I'd be Forever grateful! TIA

 

[woteva]

No need for a scan tool, just do the paperclip trick.
Thread 'Checking error codes VR/VS (Revised)' https://forums.justcommodores.com.au/threads/checking-error-codes-vr-vs-revised.22307/