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-   -   No start issue (https://67-72chevytrucks.com/vboard/showthread.php?t=841460)

mongocanfly 02-15-2023 01:25 PM

Re: No start issue
 
I have already checked pin/wire location and continuity from what psi sent me
This is what I got from them
And the are correct going by this
---
Here is the wiring, check all three wires for continuity

BROWN TO BLUE PCM PLUG 73

PINK TO BLUE PCM PLUG 61

RED TO GREEN PCM PLUG 39

PLUG LABELED A,B AND C
-----
But i needed to know which of the 3 is signal wire...
And I agree , I need all the help I can get..haha

biketopia 02-15-2023 03:36 PM

Re: No start issue
 
1 Attachment(s)
Quote:

Originally Posted by mongocanfly (Post 9178748)
I have already checked pin/wire location and continuity from what psi sent me
This is what I got from them
And the are correct going by this
---
Here is the wiring, check all three wires for continuity

BROWN TO BLUE PCM PLUG 73

PINK TO BLUE PCM PLUG 61

RED TO GREEN PCM PLUG 39

PLUG LABELED A,B AND C
-----
But i needed to know which of the 3 is signal wire...
And I agree , I need all the help I can get..haha

hope this helps

mongocanfly 02-15-2023 04:24 PM

Re: No start issue
 
Thanks..that does help.. I saw several pics like this, but they were all diff wire colors and pin functions..

RustyPile 02-15-2023 04:31 PM

Re: No start issue
 
^^^^^^^^^ I agree^^^^^^

{EDIT} I don't know how my post ended up this far down the thread.. I intended it to appear as post #26, right below Acelo's post #25..

mongocanfly 02-15-2023 05:42 PM

Re: No start issue
 
Pin C..red..has 12v with switch on
Pin A...brown...has 12v pulse while cranking
So cam sensor is working..
And I've got 12v pulse from crank sensor while cranking
So crank sensor is working..
Sighhhhhhh...
I'm bout ready to burn it to the ground

RustyPile 02-15-2023 05:55 PM

Re: No start issue
 
Quote:

Originally Posted by mongocanfly (Post 9178802)
Pin C..red..has 12v with switch on
Pin A...brown...has 12v pulse while cranking
So cam sensor is working..
And I've got 12v pulse from crank sensor while cranking
So crank sensor is working..
Sighhhhhhh...
I'm bout ready to burn it to the ground

Where did you take these readings?? You should check Both signal wires (cam sensor and crank sensor) at the ECM plug.. This will determine if the wire has continuity..

LS short box 02-15-2023 06:02 PM

Re: No start issue
 
I hate wiring also.
So is it maybe time to put it on a trailer and take it to some one with HP Tuners? They should be able to see what is working and what isn't.

mongocanfly 02-15-2023 06:42 PM

Re: No start issue
 
Rusty, I did check them at the ecm plug...I backpinned the wires there.

LS, I agree.. thats probably the next step..
I've got alot of putting together before it can leave my shop though

RustyPile 02-15-2023 08:43 PM

Re: No start issue
 
Have you discussed with PSI the possibility of a defective harness?? Since the ECM will run in another vehicle, the problem almost has to be with your vehicle..

Something is preventing the ECM firing the injectors.. Sounds like the ECM is "seeing" a wrong feedback somewhere... Pick a shop that has the experience working with these type issues and possibly one that has experience tuning (modifying) GM engine management systems.

mongocanfly 02-15-2023 08:56 PM

Re: No start issue
 
Yep

LS short box 02-15-2023 10:10 PM

Re: No start issue
 
On my first LS swap a 79 Camaro I brought it to the chassis dyno tuner with no doors, no front sheet metal, no glass and the radiator support just kind of hanging on. It was a pretty basic LS1 swap but it allowed me to drive it after the tune so I could get it to the muffler and alignment shop. Took it back later to the tuner for a few touch ups on the trans shift points.

Joyridin 02-16-2023 08:53 AM

Re: No start issue
 
Did you double check the cam sensor wires and/or crank wires to see if they are in the correct location? If they are crossed, you might have an issue there. I saw it on another forum where his harness from PSI had the cam sensor wires crossed and it would not start.

Just a thought.

mongocanfly 02-16-2023 10:01 AM

Re: No start issue
 
I checked the wiring pin location once....but I havnt doubled checked it..
But I will
The tuner guy said hes seen 3or4 harnesses in the last yr with wrongly pinned plugs

Joyridin 02-17-2023 08:21 AM

Re: No start issue
 
Quote:

Originally Posted by mongocanfly (Post 9178981)
I checked the wiring pin location once....but I havnt doubled checked it..
But I will
The tuner guy said hes seen 3or4 harnesses in the last yr with wrongly pinned plugs

If I read the story correctly, the wires were crossed at the sensor, not at the computer. I had that happen once on a LS3. Two of the wires going into the MAP sensor were crossed. It wouldn't start.

Rich84 04-19-2023 12:53 PM

Re: No start issue
 
Any updates?

mongocanfly 04-19-2023 05:09 PM

Re: No start issue
 
no... i put cranking on the backburner to try and get my painting finished..
ive got a tuner guy thats gonna look it over when i get ready

RustyPile 05-15-2023 10:07 PM

Re: No start issue
 
What's the latest on the no start? Any progress?

mongocanfly 05-15-2023 10:33 PM

Re: No start issue
 
Still trying to fix my primer disaster..


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