Project Undertow #388

[Dominicnicklyn]

I've tried using a knock-off tech2 (tech2win) to no avail.

My donor sat at a dealership for about 3 months before I came across it. Even before it had a starting issue they claimed it needed a new fuse block.

I assumed that it was due to the fact that it was "floating" around in the engine bay with no cover or mounting bracket. I'm getting one from another 06 lsj and if it doesn't solve it I'm going to find someone with a tech2.

 

[Gtstorey]

What was the problem with the tech2 clone?

 

[Goblinfanclub1234]

I have a tech2 in Colorado not sure where you are located.

 

[Rttoys]

I think he’s across a lot of water.

 

[Dominicnicklyn]

Well I'm getting some more "knowledgeable" help this weekend from my uncle. We plan on trying to diagnose with the tech2win. If that don't work then we will inspect the bus and fuse block.

Having the car somewhere nice to work on makes it much easier to get up and go out in the garage. I now have it in my heated garage. (Don't mind the clutter, family storage)

 

[Dominicnicklyn]

I've been trying to sort out what could be causing the car to act the way it is with the help on my uncle. He built an Impreza with an EG33 and some junkyard turbos and has experience with car electronics and megasquirt ect.

We started with tech2win and didn't see anything unusual. The only thing that was odd was that the EPS module wasn't communicating with the rest of the car. I don't belive that this would cause my no start issue. I checked continuity on the twisted data wires and they all checked out.

We then put dielectric grease on the plugs under the fuse block and tightened them down as tight as we could without stripping them out. We ensured some grounds and sorted through a few wires and then realized that I might have wired the fuel pump wires incorrectly. I have an 06 LSJ and the build videos used an LNF so they were different between models. We still don't belive this is a possible cause or contribution to the no start but if anyone has the correct wiring for my year and engine it would be awesome if they dropped it here.

We also used HP tuners to see if we could turn the pump on manually and we couldn't get it to work.

We ran out of ideas and time so we sat on it for a couple days. I ended up pulling the harness back out of the car and stripped the coating off to visually check for anything wrong. I rechecked pinouts for bus and ground wires along with my fuel pump wiring. I found one of the clutch pedal start switch wires being cut so I repaired that and put the harness back into the car and retried the relearn procedure and still nothing.

I'm at a standstill once again with only the fuel pump wiring and no communication with the EPS module to guide me.

 

[Rauq]

Does the throttle body move when you turn the key to on? If not, that would definitely point to your issue. If the EPS module is actually missing from the GMLAN loop and the loop is open, that might cause your no-start.

 

[Joebob]

What engine codes do you have with key on? You need the GMLAN loop complete from EPS-OBDII plug-BCM-ECU for the system to work. If you cannot pull codes, than you have at least a network issue.

Joe

 

[snirtman]

We then put dielectric grease on the plugs under the fuse block and tightened them down as tight as we could without stripping them out. We ensured some grounds and sorted through a few wires and then realized that I might have wired the fuel pump wires incorrectly. I have an 06 LSJ and the build videos used an LNF so they were different between models. We still don't belive this is a possible cause or contribution to the no start but if anyone has the correct wiring for my year and engine it would be awesome if they dropped it here.

Not sure if this will help, but here's the plug end:

 

[Dominicnicklyn]

Not sure if this will help, but here's the plug end:

View attachment 39781

This helps, but I'm unsure what pins and plugs the grey and tan/orange wires end up.

If anyone has that it would help me tremendously!

 

[RCK605]

Here are some screenshots from previous posts on fuel pump wiring.

 

[Dominicnicklyn]

Here are some screenshots from previous posts on fuel pump wiring.
View attachment 39795View attachment 39796View attachment 39797

Perfect thank you

That last one I don't have and will do some justice!

 

[Dominicnicklyn]

So it seems that I was able to pull codes. I used a cheap code scanner and was able to pull a p0452. I rechecked grounds and tightened down the fuse block plugs as tight as I could and still nothing.

I'm pretty sure that it's not a theft issue because I disabled VATS via hp tuners.

I tried running the fuel pump and turning on dash lights with hp tuners but it was unsuccessful.

The butterfly doesn't move when the car is keyed on. I'm honestly lost and don't know where to start back up from again.

Everything just leads back to thinking about how the donor car was acting this way and that it wasn't something that I've done.

 

[Robinjo]

Try turning the lights on and see if it works. Inhad a blown fuse on the BCM that would only let everything power if I did this

 

[Ross]

There are a lot of threads of builders going thru the issues with first start. You are not alone. Search for first start, read what others have had to do to get things working. The butteryfly not moving has me thinking that your car isn't communicating on the GM LAN. Using an ohm meter is good way to verify that the ground wires are working, or identify ones that are not. I took apart my ground posts, and sanded every copper loop until shiney copper, and sanded the post to bare, shiney metal. You can also use a voltage meter to verify the fuses are working at full voltage.

 

[Dominicnicklyn]

Try turning the lights on and see if it works. Inhad a blown fuse on the BCM that would only let everything power if I did this

That's an issue because I don't have any lights yet. I'm only just past the first stage in the build process.
Before I stripped down the donor I remember the lights flashing but no alarm when I opened the doors.

 

[Dominicnicklyn]

There are a lot of threads of builders going thru the issues with first start. You are not alone. Search for first start, read what others have had to do to get things working. The butteryfly not moving has me thinking that your car isn't communicating on the GM LAN. Using an ohm meter is good way to verify that the ground wires are working, or identify ones that are not. I took apart my ground posts, and sanded every copper loop until shiney copper, and sanded the post to bare, shiney metal. You can also use a voltage meter to verify the fuses are working at full voltage.

I've done everything here except with the fuses, although I replaced every fuse and ensured the relays were positioned properly.
I'm not even positive that I have all of the engine harness connected properly.

I have the large power wire that goes from the battery to the starter and fuse block post but I'm unsure what this plug is.

 

[Ross]

MAF plug?

 

[Robinjo]

Either that or injector plug.

The light switch on/off just cycles something with the blown fuse on the BCM. Just give it a try, flip them on then off and see if it starts.

 

[finazzoty]

Green wire set aside goes to c1 pin 24 and is the fuel tank pressure sensor signal
Thin of grey wire goes to ecm c1 pin 47 and is a 5-volr reference 1
I have the others figured out

I'm also looking for a fuse block ground that I dont have, its needed in part6 at 1:20

Do you happen to remember what you ended up doing with 24 and 47? I now have the same two wires hanging out and wondering what to do with them.