Hi guys. I've tried googling this and poking around in this forum, and I'm pretty stumped.2009 Corolla 1.8L started with P0300/0301/0302/0303. P0304 was conspicuously absent, but I figured it was a systemic problem, anyway. Started with plugs and coils since they were OEM and the car has like 150k+ or something crazy like that. No dice.(It occurs to me just now that I didn't check voltage at the coil pack plugs, dang.)New spark system didn't fix it? Must be air. Cleaned the air system the whole way between the air box and the plenum/intake. entire path is clean. No dice.Not spark or air? Must be fuel. All four plugs have 9.5v, all four injectors have 14 ohms. Hmm. Unplug each individually while the engine is idling.1: http://i.imgur.com/abadhyT.jpg 2: ¯\_(ツ)_/¯3: ¯\_(ツ)_/¯4: http://i.imgur.com/abadhyT.jpg This tells me that shutting off fuel to cylinders two and three, resulting in no change, means that there was already no fuel to those cylinders - probably bad injectors. Shutting off fuel to one and four, causing the engine to drag and stall, means that I'm killing fuel to one of the only two good cylinders remaining in the engine - definitely good injectors there.Okay, so injectors two and three are bad? Depressurize EFI, lift the rail, swap 1&2, 3&4 (blast them all with compressed air). Redo procedure.1: http://i.imgur.com/abadhyT.jpg 2: ¯\_(ツ)_/¯3: ¯\_(ツ)_/¯4: http://i.imgur.com/abadhyT.jpg Wait.That's the same result as last time, but the injectors are in different positions.I mean...So here's where I'm at:Air flow is good.Spark is good (with caveat to verify voltage at plugs).Injectors are actually good maybe?So what is this? *ASSUMING* I check voltage at coil pack plugs and come up consistent at all four (I CANNOT believe I forgot to do this), is this the ECU? Is it delivering bad timing? Is it delivering *good* timing based on *bad* data from something like a cam position sensor or something? How do I even begin to troubleshoot this?