LS3 throttle body on a C5
Thread Starter
Racer
Joined: Sep 2007
Posts: 320
Likes: 28
Well, I'm at a loss.
Unless I'm missing something I have my (adapter) harness wired exactly like you have yours and it's an immediate "reduced engine power" state.
I have:
Pin A = TAC Motor Control 1
Pin B = TAC Motor Control 2
Pin C = Low Reference
Pin D = TPS 2
Pin E = 5V reference
Pin F = TPS 1
Unless I'm missing something I have my (adapter) harness wired exactly like you have yours and it's an immediate "reduced engine power" state.
I have:
Pin A = TAC Motor Control 1
Pin B = TAC Motor Control 2
Pin C = Low Reference
Pin D = TPS 2
Pin E = 5V reference
Pin F = TPS 1
Burning Brakes
Joined: Apr 2002
Posts: 1,105
Likes: 114
From: Lawrenceburg, KY
I put everything back to "LS2 pinout" and it cranked/idled fine. I was able to drive around just fine. But when I hit between 5K-6K WOT, Reduced Engine Power kicks in. The codes I got were:
PCM - P1516
TCS - C1278
Oddly thought, the first WOT pull to 6K didn't trip REP. I slowed down, stopped and checked for codes (had my laptop with me scanning). But on the second WOT pull, REP did trip. I stopped, cleared the codes and on the next pull I got REP again. So I'm really confused as to why it didn't happen on time, but happened the next.
PCM - P1516
TCS - C1278
Oddly thought, the first WOT pull to 6K didn't trip REP. I slowed down, stopped and checked for codes (had my laptop with me scanning). But on the second WOT pull, REP did trip. I stopped, cleared the codes and on the next pull I got REP again. So I'm really confused as to why it didn't happen on time, but happened the next.
Last edited by ChrisLSx; Oct 9, 2017 at 11:51 PM.
Instructor
Joined: Oct 2010
Posts: 247
Likes: 44
From: Vancouver Island British Columbia, Canada
Which years are your cars? Same, different? Here is a link to some alternate ecm/pcm pinouts and as you can see by looking they're not all the same. http://corvetteforum.shelor.net/Corv...ts/Default.asp
'05-'06 GTO guys can just bolt these LS3 throttle bodies on and go although they already had an LS2 TB as opposed to the 78mm LS6 TB and they have an E40 PCM. There's some interesting reading in this http://www.ls2.com/forums/showthread...e-set-up-donor thread from a pretty knowledgeable Aussie.
'05-'06 GTO guys can just bolt these LS3 throttle bodies on and go although they already had an LS2 TB as opposed to the 78mm LS6 TB and they have an E40 PCM. There's some interesting reading in this http://www.ls2.com/forums/showthread...e-set-up-donor thread from a pretty knowledgeable Aussie.
Burning Brakes
Joined: Apr 2002
Posts: 1,105
Likes: 114
From: Lawrenceburg, KY
I have a 2004, his is a 1999.
This has been a very odd experience.
My LS3 TB "works" (cranks/drives but no high RPM WOT) wired like an LS2 TB. If I wire my LS3 TB like HPS', I immediately get REP (don't even have to crank it).
HPS' LS3 TB works wired like he has it, but if he wires it like an LS2 TB it immediately gets REP.
None of this makes any sense.
This has been a very odd experience.
My LS3 TB "works" (cranks/drives but no high RPM WOT) wired like an LS2 TB. If I wire my LS3 TB like HPS', I immediately get REP (don't even have to crank it).
HPS' LS3 TB works wired like he has it, but if he wires it like an LS2 TB it immediately gets REP.
None of this makes any sense.
3rd Gear
Joined: Oct 2014
Posts: 3
Likes: 0
I have a 2004, his is a 1999.
This has been a very odd experience.
My LS3 TB "works" (cranks/drives but no high RPM WOT) wired like an LS2 TB. If I wire my LS3 TB like HPS', I immediately get REP (don't even have to crank it).
HPS' LS3 TB works wired like he has it, but if he wires it like an LS2 TB it immediately gets REP.
None of this makes any sense.
This has been a very odd experience.
My LS3 TB "works" (cranks/drives but no high RPM WOT) wired like an LS2 TB. If I wire my LS3 TB like HPS', I immediately get REP (don't even have to crank it).
HPS' LS3 TB works wired like he has it, but if he wires it like an LS2 TB it immediately gets REP.
None of this makes any sense.
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Burning Brakes
Joined: Jan 2008
Posts: 1,235
Likes: 51
Sorry for the *** question, but what will a ls6 cam exhaust intake bennifit with a ls2/ls3/ls7 throttle body? Also, any bennifits from one to the other?
I'm running a Haltech Killer Bee 2 with Ls7 style maf card.
Thanks
I'm running a Haltech Killer Bee 2 with Ls7 style maf card.
Thanks
Running Guns & Moonshine
Joined: Aug 2001
Posts: 12,675
Likes: 7,306
From: CT
I did an upside down install. In my case I used the Caspers LS2 to LS1 adapter harness and it has worked without issue both on stock tune with FAST intake and later with A&A P1 and mafless EFI Live tune. I unplugged it all and also disassembled the TB (Gold plate) this Spring intending to paint but did not. Now with it back together I get the P1516 rep fail when I go WOT. Have not used the multimeter yet, but did check pins visually - all appears good, just doesn't do what is needed.
Racer
Joined: Jun 2007
Posts: 371
Likes: 22
From: Woodstock GA
Ls3 gold blade working fine
so far so good.
Starts up, drives and one WOT so far.
i’ll report back after some more miles and WOT piulls.
definelty feels better, but I have a sheet metal 102mm intake.
Starts up, drives and one WOT so far.
i’ll report back after some more miles and WOT piulls.
definelty feels better, but I have a sheet metal 102mm intake.
Last edited by maxgee; Jan 6, 2019 at 11:32 PM.
Racer
Joined: Feb 2008
Posts: 457
Likes: 34
From: Hamilton Montana
Mine will go into REP mode 80% of the time I go WOT, I haven't tried applying the tuning settings recommended by Pekka_Perkeles yet though.
Burning Brakes
Joined: Oct 2005
Posts: 1,089
Likes: 82
From: Kauhava, Finland
Go ahead, it'll be fine. You will get rid of REP at near or at WOT.
Racer
Joined: Jun 2007
Posts: 371
Likes: 22
From: Woodstock GA