So i pulled the engine from my Caprice and also the wiring harness. Now i want to convert it to a standalone harness but as it's my first time this i not so straightforward.

As the LT1 is by far not popular but where i'm from (Belgium) it's what i get to work with. Finding information about this engine and the pin outs is not so easy.
My best scource so far is lt1swap.com, specifcally this page with wiring schematics:
http://lt1swap.com/95impalalt1.htm

But my harness is different from those schematics although quite similar.

The biggest question i have is how do i know what i can remove from the harness and what not?
And is it likely that faults will start to pop up in the ecu when certain connectors are not connected, how do i get round that?

 

Ok, just found the pinout for the pcm on lt1swap through google. So my first question on what to remove has been answered

 

Hello Dieter,

Small world, I used to live in Mons-Casteau back in 1994-97. Yes, faults will show up for the things you are deleting from your harness. But we deal with those by modifying the program running inside the PCM - we use an application called "HP Tuners" though there are other apps that can also do this. Basically, HP Tuners tells the Powertrain Control Module to either ignore those faults or to not illuminate the Check Engine Light / Malfunction Indicator Light. In the best case, these faults will not even show up when a DTC code reader is connected to the On Board Diagnostics (OBD) II connector.

Here below is what my local tuner person who has HP Tuners did to my PCM:

Startup and at temp idle raised 100 rpm
PE Delay set to zero
Cat Overtemp Disabled
All EVAP, EGR, Fuel Sender, and Rear O2 codes deleted
Speedo and shift points corrected for current tire/gear
Max line psi disabled in case of MAF failure
VATS turned off no relearn necessary - Vehicle Anti Theft System
Fans Activated

For this, the charge was $175 USD. His effort only cost $75 but he had to buy two "credits" for $50 each from the HP Tuner company to "license" the new operating system inside my PCM.

So I think your difficulty will be to find somebody in Belgium that has HP Tuners or a similar program to modify your PCM.

Rick

 

Hey Rick - thanks for the info. I'm slowly trying to find someone nearby who has experience with the reprogramming the PCM. I was able to find a dedicated Dutch forum of the Caprice/Impala model but things seem to have died out at lot since 2016.

 

have you looked into the eficonnection 24x conversion so you can ditch the optispark stuff and run a ls 0411 ecm? not exactly low buck but more support and tuneability
if you're staying stock it might not be necessary but may be worth a look at this stage

 

Hey Dieter,

Don't limit yourself to searching for places that deal with only Caprice and Impala vehicles. I'm certain that there are European groups that support other GM vehicles running later LS style engines that can assist with reprogramming your LT1 engine. I'm fairly certain that HP Tuners is backwards compatible to your LT1 engine.

Rick

 

You must have miss-posted. This is irrelevant to the op and his post was in 2018. lol

 

I must have been sleeping lol .. I deleted my irrelevant message