Creepycrawler

Hey all, Im having some issues, thinking that my computer isnt actually writing even though it says job complete. I went in and changed vats to none and deleted the EVAP stuff under engine Diagnostics. but when I try to start it theres no spark or injectors opening. I pull up the computer in the scanner and it shows 140 ish RPM while cranking. Also shows 12.5 timing advance but when you check the plugs there is no spark. I have 12v to the injectors and the coils (verified with power probe) I have all the other pink wires and orange wires twisted and taped together to a hot wire direct to the battery. I hot wired the fuel pump also. Vehicle is a 2004 5.3 trailblazer, motor and trans are still in the vehicle, I wanted to do a test fire with the Vats removed to make sure it still worked after I trimmed down the harness as per LT1swaps.com I drove this thing into the garage 4 days ago, now it wont run. any ideas ? any way to read the computer while its on the vehicle? when I try to read it the button isnt highlighted on the VCM Editor, but the Write button is

Creepycrawler

I tried "write entire" and then I figured out how to read the tune I just wrote onto the ECU so I am gonna attach it here, it still wont start, no spark. I also pulled up the scanner while I tried to start it and made a Log, Ill attach it too. Any help or Ideas would be greatly appreciated.

Creepycrawler

did more testing today verified 12 volts at the Coils and Injectors, also have 12 and 5 volts at the MAF. Checked the coils with a test light, checking for the computer to ground them to fire them, no flash on the test light. Im really thinking Im having computer issues, as it is reading the Crank position, but refusing to fire the coils. Thoughs?

G Atsma

You will always have voltage at the coils and injectors. They operate by GROUNDING that voltage. Make sure all connections are secure.

Creepycrawler

I checked the hot side of the coil for power, then reversed the test light and checked the coil control from the ecu to the coil to see if the computer was grounding the coil while cranking, it didnt.