60 replies to this topic

[Truckin1999]

Well Jeff (MoneyWellWasted) is no longer going to do the V8 swap so I'm buying the engine from him for a reasonable price and its going in the Blazer right now.

I pulled the motor apart today and found some good and bad things. It has been recently rebuilt which can be a plus or minus depending on how you wanna look at it. Do to the size of the current bore/crank bearings/rod bearings I would think it may have been rebuilt more than once. On the good side, it doesn't look like there have been too many miles put on the engine since the rebuild. I decided I am gonna skip the machine shop and just start throwing new parts at it. I may or may not be having some work done to the heads to handle the amount of lift I'm using. I ordered comp springs and retainers to see if that will give me the clearance I need. It should be a pretty healthy motor when its done. But that's all I'm gonna say on that for now.



My real questions lie in the wiring. I will be sending the ECM to CPW to get reflashed. I actually have 2 since I have all the L31 harness/ecm. I would just like some more clarity on how to mod the harness. I don't want to pay to have it done. I have searched quite a bit, and all I keep coming up with is the info stickied in this section. So I know which color wires go to which number pins. What I don't know is how the connector pins are actually numbered, and how I remove/replace the wires. Would it be easiest for me to just pull the injector pod and wiring off both harnesses, then attach the V8 pod to my harness? I have yet to find any pictures or any details on how exactly the process goes. Hopefully someone here can help me.


Thanks,
-Sean-

Edited by Truckin1999, 14 March 2012 - 08:16 PM.

[civicslayr07]

u know i was having that same problem. maybe mwood will chime in here. *crosses fingers*

[Dw©]

Send your harness and ecm to Jims performance. He's WAY faster and cheaper than CPW.

http://www.jimsperformance.com/

Dw

[cknaffle]

Get it all figured out. There may be another one coming your way in the near future.

[MWood]

Once you tear the harness apart near the injector pod, it is really easy to figure out. The actual injector pod is numbered by cylinder. To pull the pins/wire out, you need to pull the white retaining clip off from the side then that will allow you to pull all the wires out. Just go one by one removing them from the V6 pod to the V8 pod. Then add the two extra wires for cylinders 6 and 8 I believe. ( Its actually 4 extra wires, 2 to control and 2 switched 12 volt).

You can save a bunch of money by doing it yourself. I didn't realize how easy it was until I had to troubleshoot my harness after paying to have it done. Hopefully that helps.

[02 Wherry]

Exactly what Mike said. Just be patient and draw diagrams or take pictures so if you make a mistake you can go back. Everything is labled by cylinder and wire color.

[Macs05Z]

Exactly what Mike said. Just be patient and draw diagrams or take pictures so if you make a mistake you can go back. Everything is labled by cylinder and wire color.

I am wondering the same thing. I want to do my own harness work, but I dont see a diagram for the silver pcm on here. When you put the new wires in the injector pod where do they go into the computer. If anyone here has a diagram for the L31 swap using the silver pcm Id appreciate it.

[MWood]

Whoever you have reprogram your computer should give you the diagram for it. Or you can talk to bvd80, i think he used the silver computer.

[bvd80]

Exactly what Mike said. Just be patient and draw diagrams or take pictures so if you make a mistake you can go back. Everything is labled by cylinder and wire color.

I am wondering the same thing. I want to do my own harness work, but I dont see a diagram for the silver pcm on here. When you put the new wires in the injector pod where do they go into the computer. If anyone here has a diagram for the L31 swap using the silver pcm Id appreciate it.

Hey,

Heres the pinout for the injector wires on the PCM....all injector wires are on the BLUE pcm connector.

Injector 1 = pin 36
Injector 2 = pin 3
Injector 3 = pin 4
Injector 4 = pin 43
Injector 5 = pin 76
Injector 6 = pin 37
Injector 7 = pin 44
Injector 8 = pin 77


Hope that helps...

Edited by bvd80, 14 September 2009 - 05:33 PM.

[bvd80]

This will really help...its the whole pinout for the silver pcm!! This is what I used for my swap. It is a 2002 Vortec V8 Express van.

Attached Files

•  silverpcm.gif   64.27K   80 downloads
•  silverpcm2.gif   64.23K   52 downloads
•  silverpcm3.gif   73.43K   33 downloads
•  silverpcm4.gif   56.85K   31 downloads

Edited by bvd80, 14 September 2009 - 04:16 PM.

[Truckin1999]

You guys rock! Thanks much for the info.

Are the pins on the black ecm the same as the above diagrams for the silver ecm? So with the connector facing me the pins start at 1 in the bottom right?

[Truckin1999]

Send your harness and ecm to Jims performance. He's WAY faster and cheaper than CPW.

http://www.jimsperformance.com/

Dw

At Jim's they can reflash the ecm for the swap as well as make a pretty good tune for a custom engine (mine won't be very close to stock)? I was going to have Jared at CPW do the programming because I had previously spoken with him and he has done it so many times he can come up with a good tune w/o putting the Blazer on a dyno. If Jim's is as good as CPW and can do it faster and cheaper then by all means I'll go with them.

If you can vouch for Jim's then that's where I'll go.

Edited by Truckin1999, 14 September 2009 - 06:09 PM.

[Truckin1999]

Get it all figured out. There may be another one coming your way in the near future.

This is what I live for. As far as I'm concerned building engines and swapping them is more fun than it is work. It will be good to get it all sorted out in my own swap, then I'll be ready for everyone else.

[bvd80]

You guys rock! Thanks much for the info.

Are the pins on the black ecm the same as the above diagrams for the silver ecm? So with the connector facing me the pins start at 1 in the bottom right?

Nope the black PCM is totally different. The pin numbers are all labeled on the connector where the wire enters it. Can't go wrong!

[Truckin1999]

You guys rock! Thanks much for the info.

Are the pins on the black ecm the same as the above diagrams for the silver ecm? So with the connector facing me the pins start at 1 in the bottom right?

Nope the black PCM is totally different. The pin numbers are all labeled on the connector where the wire enters it. Can't go wrong!

Yatzee!! Thanks man!

[Macs05Z]

Thanks alot. So besides the pod wires for the injector, what other wire do I need to run and where? What are the 2 additional 12V wires go and y. And can I wire a ford taurus efan into the silver pcm. Thanks again. I just dont want to wait and hope to have these questions answered when i have the truck apart.

Edited by Macs05Z, 14 September 2009 - 09:36 PM.

[Truckin1999]

Well I got a bunch of packages from Summit yesterday. Its like christmas opening em all.

Unfortunately the balancer was on backorder and I didn't realize it. Also the Flexplate I got was for a 2pc rear main. I ordered the correct parts and will be sending back the other flexplate today. Still waiting on the rotating assembly shipped from NV. Hopefully by this weekend I'll be assembling the engine. Gotta get on the ecm programming asap. Moving along though.

[cknaffle]

So does this mean things finally settled down for you a little bit, or are you still running yourself half to death keeping everybody happy?

[MWood]

Thanks alot. So besides the pod wires for the injector, what other wire do I need to run and where? What are the 2 additional 12V wires go and y. And can I wire a ford taurus efan into the silver pcm. Thanks again. I just dont want to wait and hope to have these questions answered when i have the truck apart.

The switched (when the key is on) 12 volt wires are actually what powers the injectors and they get wired to the fuse box under the hood. Just need to find 2 slots that are hot with the key on. I wouldnt recommend splicing into other wires because I think the voltage would drop.

The other wiring that needs to be done can be found in the sticky. Basically extending some wiring.

[Macs05Z]

Thanks alot. So besides the pod wires for the injector, what other wire do I need to run and where? What are the 2 additional 12V wires go and y. And can I wire a ford taurus efan into the silver pcm. Thanks again. I just dont want to wait and hope to have these questions answered when i have the truck apart.

The switched (when the key is on) 12 volt wires are actually what powers the injectors and they get wired to the fuse box under the hood. Just need to find 2 slots that are hot with the key on. I wouldnt recommend splicing into other wires because I think the voltage would drop.

The other wiring that needs to be done can be found in the sticky. Basically extending some wiring.

Thanks MWood, I have read the threads over and over, I was just curious about the injector wires to the newer silver box. I understand the rest of the wiring like the o2 wires. Thanks again.