996 Fuel Injectors/Throttle Body question
I have a 748s chassis with a 996 transplant. Earlier this week she started but died a few seconds later and hasn't started since. If I spray some starter fluid into the carbs she'll start for a few seconds so I'm pretty sure it's a fuel supply issue and not electrical/relays/plugs. Fuel pump whines when I turn the key so I'm focusing south of the tank for now.
Now that I have the tank and airbox off I'm a little confused at what I'm looking at and the Haynes manual isn't helping. The throttle bodies have 4 injectors (green heads) but only 2 of them have electrical connections. Should I clean/replace all 4 injectors or are the 2 that have electrical connectors the only ones that are actually doing work?
Any other usual suspects that I'm not thinking of?