Heres the scoop. 07 LY6 E38 ecm. Have Crank, Cam signal. Has spark. No injector pulse. VATS is disabled and car will run if you spray brake clean in the intake. My Modis scanner shows that it has injectors pulse. HP tuners shows injector pulse but i never get a noid signal. All injectors have power during cranking and key on.

Things im not sure of. Accessory wakeup serial data wire?
What does this do and what should it be hooked too?

With a volt meter hooked to power and to the ground side of the injector wire it will show ground with key on. Normal? But the ground will not light a test light.

Any help would be greatly appreciated.

THanks David

 

Here is what I found on the accy serial data wire. Looks like it shouldn't have to be connected.

The accessory wake up line is an accessory fed power feed to the ECM and TCM (etc).

It is there in most cases to support "wake up" of low speed serial data when the key is on accessory, vs ignition on/engine running.

 

did you do a full flash after you killed the VATS?

 

I didnt do the tune myself. I had a local tuner do it. I will have to ask him.

 

Asked this question on another forum and I was under the impression that he had it redone.

 

It was a full flash. Im lost. Guess this thing is just destined to stay in the garage

 

Have you checked the fuel pressure at the rail? You are showing injector pulse while cranking? My LY6 cranked and ran from the first time I put power to it. I do not have the accessory wakeup wire connected.
I just cranked my L76 on my test stand over the weekend and it was pissy about cranking. It finally did, but it was difficult about it.
Do you know if you have your fuel pump set to "Fixed"? Seems like my LY6 was not and I had to change that setting.
Bounce some more ideas off me and I can check them against my LY6 setup.

 

starter enable wire.... Needs to see a ground? Took it to a friends shop and he came up with that and now it starts and runs. Did you have to do this also?

 

just read your truck swap and seen the starter check disable... Guessing that would make it so i dont have to ground that wire?

 

Yes, the starter check disabled kept me from having to run the ground wire...Great news, glad you got it running...

 

Don't know if you will be back online, but I just went through my LY6 startup today. Without your help it would have taken me days to wring it out. The grounding of the fuel pump relay and starter relay ECU pins were the last key issues.
Thanks much.
v10rodder

 

thank you We where racking our brains out with the same stuff ripped apart the whole harness and then I found this post.

 

Glad to help, the info is here if you search for it

 

Found your thread, and it pointed me into the correct place after a week.ran the wire, no go, shot the Camshaft position no go, changed the disable engine crank, and off the beast went. cheers to all

71 GMC stepside LY6/6L90