Code 12 for the ECM means its okay. The fuel injectors, two sets, pass side & drvr side, are powered by a relay each and a fuse to one side of the injectors. The other wire of the injector goes back to the ECM.
The ECM places a "low" on this wire, thus, creating a difference in potential and the injector opens for milliseconds. Only a "noid" light will show this event. One side of the engine is a green wire and a black wire, the other side is purple wire and a black wire.
As a test, you can measure the injector coi; resistance with a DMM, digital multimeter, and measure 12-14 ohms for each coil. Also, measure into the disconnected harness to be certain continuity to the ECM. Having power to one side of the injector and control voltage on the other side are important.
On the intake side, be sure the MAF meter is plugged in the circuit as well as the intake air. Plus, be sure the bellows has no holes and the intake track from MAF to the throttle body is "airtight."
It reads like the cold start injector is working good. Fuel pressure reads good. I'm sure in swapout of the chip, the operation went smooth and no bent pins, or, if the ECM is from a different vehicle, the chip was changed as the chip goes with the VIN, not the car.
Hopefully, you didn't crunch any wires from the wire harness when replacing the trans. The wire harness does come close to the b/housing & engine interface.
Be sure spark is going correctly to each cylinder and at the proper time. You didn't break any ground wires or leave any off did you? There are a few fusible links at the starter solenoid terminal with the posotive battery cable. There may be one broke.
ECM is not going to generate any codes until the engine is running. Pull the spark plugs, dry them off, blast each cylinder with shop air to dry out. Charge the battery. Reinstall plugs, mash throttle to the floor, and attempt to start. Retrace your steps through the trans swapout just to be sure you didn't miss anything or left something out. I wager it will run.
Oh, Welcome to the Club, Newbies buy the first round. You'll enjoy it here. Let us know what happens.
PS., Hopefully, the IGN position of the ignition switch is in good repair. I'd hate to read later the start ign signal is good, but the "run" position is bad.
Give a man a rescued dog for the health of both their souls. May 2017 ROTM Winner - Thank you!
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
CUBS - 2016 World Series Champions - Thank you, Joe Madden … enjoy your next chapter.