The connections have to be really tight and might need to be disconnected and adjusted tighter with a pair of pliers before reconnecting.
Also have a close look at the fine wire filaments inside the bulb. Sometimes they're broken but still touch together enough to make them work intermittently...
Try washing the rubber cap seal in metholated spirits and drying it thoroughly before refitting it.
I've found if there is brake fluid on the seal it slips out of position when tightened.
The brown stuff around the radiator cap could be the residue from the three tablets Holden recommended adding to the radiator coolant. Rumour has it they consist of compressed ground up walnut shell and are precautionary to sealed up any minor leaks that might occur.
10% chance its a dud CAS.
90% its the wiring loom connection where it bolts to the bottom of the DFI.
If someone's ever wiggled it a bit when disconnecting that's where the problem will be.
Tighten those connections with a fine pick or probe.... even if you reckon they look tight.
Looks to me like a cheap ultrasonic cleaner dressed up with a pulse power source to cycle the injector.
A couple of things to be wary of. Not all ultrasonic cleaners are equal.
The good ones have circuitry to send variable sound waves of the right levels to drive dirt and grease from the
surface...
With the drop in revs happening about 10 minutes after starting it might be something related to the oxygen sensors activating as the car's computer goes from open to closed loop mode, trying to bring the fuel to air ratio back to where it should be.
Are all the engine's vacuum hoses connected...
Looks like it will be a big event.
That's good that there will be some fanfare at the end.
Hopefully a better sendoff than the poor old Falcon had....:)
If the light has come on it will have thrown a diagnostic trouble code that can be read.
That's the best place to start. Don't go replacing parts or transmissions just yet.
How long has it been since it had a full service? The old girls love a bit of pampering.
(plugs,leads,air,fuel filters and throttle body clean)
If she's right in that department I'd check for any leaks/splits in the engines vacuum hoses and air intake hose.