88 RRC 4.0
I've replaced cap, rotor, and wires all having no affect on the idle. Hooked it up to a scope and noticed that killing the #3 cylinder does not affect it at all, it doesn't seem to care if it's hooked up or not! Changed out the #3 plug with a spare and it still runs the same with the plug wire hooked up or not. It runs with no missing or anything under load, it just happens at idle
I pulled the power plug to the #3 injector thinking that the problem is now fuel related and started it up. It didn't seem to make a big difference so I pulled the #5 injector plug and it ran essentially the same (was hoping for a big difference). I'm running out of ideas that are cheap/easy to do to this thing, is there anything else I can do that I might have missed? The idle has been low ever since I replaced the stepper as well and swapping steppers from my dad's D90 makes no difference.
Just listened to the injectors and they all seem to be firing normal but we're now thinking that a bad spray pattern could be the culprit.