Originally Posted by 86White_T/A305

hey guys,after a week of working on my car swapping this ls1/t56.i finally tried to start the car tonight and to my big disappointment the car wont start.

i bought the ecm from spareecm and had all emissions,vats,skip shift,rear o2 etc deleted.during cranking the motor spins as if its not making compression...i dont have exhaust on it yet just open header.atfirst i had my feed and return lines backward on the vette filter lol and a slight leak.i fixed that and still no luck when i tried to start it again.

then i pulled number #1 plug..and its bone dry which indicates im not getting any fuel from the injectors.what would tell the ecm not to fire the injectors and does it matter if i dont have any belts on to see if it start and runs for a minute or 2?
Injectors should fire at the start regardless of other issues as long as the crank sensor is connected and reading good

the only mods is a ls2 maf,i dont have the o2 sensors plugged in aswell but i doubt that would cause the ecm not to fire the injectors right?
Car will run without the HO2s and MAF connected. Get them connected ASAP, but they're not essential for the first fire

need help of what to check for..ive spent hours today hoping id be driving and fine tuning..cant think straight anymore.i got 2 days left to get my car done and out.any suggestions would be great.thanks

stock harness that i stripped down myself.im wondering if there is something i missed that the ecm needs to see to spray fuel.all the tank sensors were deleted.my starter wire is bypassed but the clutch position sensor is hooked up.do i have to press the clutch in still?
No, you dont have to push the clutch in with the switch bypassed.Its a safety feature that should be used though

i simplified all main battery,ignitions,and ground wires into those 3 fuses and upgraded the wires for better current.nothing is blown.looking over my ecm pinout on the blue connector,pin 30 is dark blue fuel enable control. do i need this wire or is it part of the tank sensors on the 4th gen?
Fuel enable is VATS. With it disabled in the PCM, this wire gets deleted

well i havent had any luck getting this thing to start

Pocket if your are reading this i have a few questions about the harness.every sensor has its ground and 12v referrence at the ecm that i tested.i have a cheap obd2 code reader and he only code that came up was a p0118 for bad cts.im using the 3 wire cts and had 2 wires backwards,fixed it and the code has gone away.i dont know what else would tell the ecm not to fire but can anyone tell me if i need these wires hooked up to anything:

ecm blue connector:
pin 34 orn/blk neutral safety switch-do i need this with man trans?
No

ecm red connector:
pin30 dk blu fuel enable-does this have to be wired up and to what?
pin 53 gra/blk ignition retard signal-what does this mean and do i need it?
Traction control IGN retard, delete

im out of ideas..and not having a scanner makes it hard to diagnos.everything should be deleted.

also on the red ecm connector pin 51 tft sensor?is this needed for anything?
4L60E pin L, T56 not reused

really hoping you guys can help me figure out if either i have a small wiring issue or if my ecm wasnt tuned right from spareecm.com

yea i tried putting fuel in the throttle body and cranked it over but still got nothing..not even a stumble.just seems like the motor is turning over very freely..no compression :S
Do a compression test, thats the biggest worry right now

ive been checking all the grounds on the sensors,all ignitions,..fuel pressure is normal.im thinking i have a junk ecm or something isnt wired for it to fire injectors and now im thinking have no spark aswell.
Use a meter to speed things and know for sure good/faulty connections. Test for 12v IGN on the individual points like injectors, crank connector, coils etc