Hex Hacker

I have found that you can interchange most Accelerator Pedal, TAC Modules, T-Body, and PCM's.

I have used a 2000 Corvette T-Body on a 2006 Silverado and I have used 1 2006 5.3L T-Body on a 2005 CTS-V calibration.

I would have a LS2 T-body on a older PCM, but I just tossed/scrapped 20+ T-body's

All of the changes that need to be made are in the Engine Segment and the Engine Diagnostic Segment

ctd450

iTrader: (1)

Good info. Ever mess with the Gen IV stuff that doesn't use a tac? I've got a somewhat recent thread about which pedals can work in place of a truck pedal using an '08 E38 PCM. A few good leads but more options never hurts.

https://ls1tech.com/forums/conversio...l-options.html

BigEd_72455

iTrader: (7)

Why would you throw them away? You should have put a listing up on classifieds for the different t-bodies you had and offered them up for cheap and gotten a little bit of money out of them.

aknovaman

iTrader: (7)

Most is a pretty broad statement.

The throttle bodies are at the recieving end of the line as a servo motor and also include a TPS to tell the PCM actual TB % opening info back to the PCM. If you interchange the gas pedals, with an operating system and PCM file that is expecting a specific voltage at closed and fully open throttle it will not work correctly. Newer gas pedals have a resisitor (as seem in the schematics and measured with an ohm meter) built into the pedal that either elevates or limits the closed and wide open voltages received by the TACC. Mismatching the pedals, PCM file settings and TACC usually spell pedal OBD2 codes and limp mode operation. This has been tried and proven many times over.

So unless you are able to actually crack into the hex code and modify the pedal and TB voltage threshold/criteria in the PCM file and the non-programmable TACC, I doubt your findings.

This appears to be your oportunity to educate us, so plz prove your findings with specific TACC, pedal examples other than those above.

Hex Hacker

The operating system has nothing to do with it. The OS could be the same between a Vette style and a Truck style T-body. So how does your logic work with that. I worked with and supplied lokar's ETC engineer with information to get the pedal they offer going. The TAC module has nothing to do with the reduced power mode. I think HPT may add the needed parameters shortly. We will need to make sure that you can not brick the PCM by changing these parameters first or you will be paying to get it unbricked

Hex Hacker

The issue Jim had in this thread was a setting. This would have been an easy fix for me to do.
https://ls1tech.com/forums/pcm-diagn...ight=caleditor

aknovaman

iTrader: (7)

Ok so how do you get around the incompatibility that has existed since dbw has been made by gm.

feel free to pm me to discuss further.

ls1nova71

iTrader: (4)

This is a VERY broad statement to say the least. This is the kind of information that is going to cause a lot of people grief. True, you may be able to interchange some parts, but I would not say most. I know for a fact that a 2003-up truck throttle body won't work with a 2000-2002 truck TAC or OS, and vice-versa, so just randomly telling everybody that nothing matters and you can use what ever you want, just doesn't seem like a good idea. It's still better to keep the parts matched as GM designed them in my opinion.

Hex Hacker

It will work without an issue. The OS has nothing at all to do with it.

gofastwclass

iTrader: (2)

...so what is the magic silver bullet then? I've seen and heard of people unsuccessfully trying various combinations of pedals, TAC modules, throttle bodies and PCM OS's trying to get something to work. Each time it worked we thought we were on to something only to discover we had "happened" on the parts GM listed for that combination.

Honestly, I almost won't buy a DBW engine unless I can get everything from the same vehicle for exactly that reason. If I could use car pedal x (like a Monte SS) or something inexpensive (non GTO or Corvette) that fits the firewall of most swaps with any (or even most) PCM's with any (or even most) calibrations I (and many others) would be all over it.

What you have listed sounds great, but without part numbers and OS numbers to reference it's quite vague and thus difficult to replicate in the field.

garys 68

iTrader: (1)

Why did you have 20+ LS2 TBs that you threw away?

ls1nova71

iTrader: (4)

If by "work without an issue" you mean as soon as you pressed the throttle pedal past half way the throttle body would shut and not work again until the ignition was shut off and turned back on, then yes it "worked". Trust me I tried it many different ways and it did NOT work.

gofastwclass

iTrader: (2)

^^^Asked by one of the handful of people I personally know who has tried .^^^

24 hours and no response to direct questions on HOW to do this from Hex Hacker. Hmmm??? This little tidbit of knowledge would be a wonderful holiday present for many of us, please share.

aknovaman

iTrader: (7)

Guess he does not want to answer our questions.

Not much info over here on his post either.

http://www.performancetrucks.net/for...ontrol-524942/

Hex Hacker

I helped Lokar with the pedal assembly they have.

I will give the information to Bill at HPT to add the needed parameters shortly. I would hate to have someone brick a PCM and then need to have someone unbrick it.

Hex Hacker

I hope this will help explain it

I have it all figured out in hex and tested on a few vehicles. The current truck is a 1996 C1500 with a 2006 LQ9, a 2006 TAC module, 2004 PCM, 2005 OS, 2005 CTS-V Calibration, 2006 T-Body, and unknown pedal

This truck had all 2006 parts to start with, so I would assume it had a 2006 APP.

This is a little information

TAC Module 12588923
fits
CADILLAC(2)
ESCALADE(2)2005-2005

CHEVROLET(24)
AVALANCHE(2)2005-2005
AVALANCHE 2500(1)2005-2005
SILVERADO 1500(5)2005-2005
SILVERADO 1500 HD(1)2005-2005
SILVERADO 1500 HYBRID(1)2005-2005
SILVERADO 2500 HD(3)2005-2005
SILVERADO 3500(3)2005-2005
SILVERADO SS(1)2005-2005
SUBURBAN 1500(2)2005-2005
SUBURBAN 2500(2)2005-2005
TAHOE(3)2005-2005

GMC(23)
SIERRA 1500(6)2005-2005
SIERRA 1500 HD(1)2005-2005
SIERRA 2500 HD(3)2005-2005
SIERRA 3500(3)2005-2005
SIERRA DENALI(1)2005-2005
YUKON(3)2005-2005
YUKON DENALI(1)2005-2005
YUKON DENALI XL(1)2005-2005
YUKON XL 1500(2)2005-2005
YUKON XL 2500(2)2005-2005

TAC Module 12945405 fits the following. This TAC module is used on PCM's that have the same OS as a truck. The T-body is different, but the Engine and Engine Diagnostic SEGMENTS are the portion of the calibration that works with the TAC module

CADILLAC(2)
CTS V(2)2004-2005

CHEVROLET(12)
CORVETTE(10)1997-2004
CORVETTE Z06(2)2003-2004


TAC Module 19245406 fits the following

CADILLAC(2)
ESCALADE(2)2002-2002

CHEVROLET(44)
AVALANCHE(1)2002-2002
AVALANCHE 2500(1)2002-2002
SILVERADO 1500(7)2000-2002
SILVERADO 1500 HD(2)2001-2002
SILVERADO 2500(6)2000-2002
SILVERADO 2500 HD(6)2001-2002
SILVERADO 3500(4)2001-2002
SUBURBAN 1500(4)2000-2002
SUBURBAN 2500(5)2000-2002
TAHOE(7)2000-2002
VAN G3500 1 TON EXPRESS(1)2001-2001

GMC(46)
DENALI(2)2001-2002
SIERRA 1500(7)2000-2002
SIERRA 1500 HD(2)2001-2002
SIERRA 2500(6)2000-2002
SIERRA 2500 HD(6)2001-2002
SIERRA 3500(4)2001-2002
SIERRA C3(1)2001-2001
SIERRA DENALI(1)2002-2002
VAN G3500 1 TON SAVANA(1)2001-2001
YUKON(7)2000-2002
YUKON XL 1500(4)2000-2002
YUKON XL 2500(5)2000-2002

GM has a 512kb PCM and a 1meg PCM used on these vehicles
If you look at the Corvette. You will see that the same TAC module was used on all of the operating systems and all of the PCM's. The 2004 PCM is a 1 meg. The Corvette used multiple throttle bodies, but they are similar in design.
Then if you look at the CTS-V you will see the same TAC module used as the 1997 Vette and this car uses a 2005 Truck OS
That covers the 512kb, 1m PCMs, multiple T-bodies and multiple operating systems. The OS is not tied to the TAC module

This could be an argument
The 2000 to 2002 Trucks ran 1 style T-body and the 2003 up ran another. the TAC modules. I tested this and I have run the 2003+ TAC module on a 2002 truck and did not have an issue.

Most of the 1999 to 2003 512kb operating systems are used on both cars and the trucks and they use different TAC Modules and T-bodies

The APP
They all interchange from what I have run across. Every APP that I have tested had all 3 APP sensor circuits. Most of the harnesses have all of the circuits wired in. The Calibration does not reflex the 3rd sensor.
I had a 2003 truck in that would go into reduced power mode. We could not catch it on the Tech II even in a snapshot. The truck had the 3rd circuit wired up. I built the truck as a 2004 Corvette and sure enough I could see the 3rd APP sensor.
I disconnected the 3rd APP signal wire and the truck drove just fine.
I ended up replacing the APP to fix the truck. The APP on the truck was an aftermarket part and had been replaced prior to coming to me.

I have no problem with someone wanting to keep all of the parts together. They may want to match the T-body and the TAC module


This is the interesting part and I/we have performed extensive testing

When you install a car calibration in a truck that uses the same OS the TAC system will fault out.
If you look at all of the TAC data you will see the issue.
Average APP 0% to 100% --> this is the Average of the 2 or 3 sensors
Indicated APP 0% to 100% --> this is the calculated APP used by the system

Desired TPS Angle 0% to % --> this is the commanded throttle position by the TAC module
Indicated/Actual TPS Angle 0% to 100% --> this is the return signal from the TPS 1 & 2 calculated by the TAC module. This should match the Desired angle

The TPS will follow the APP from 0% to about 75% just like Jim PA had. Then the TPS drops to 0% and it may show reduced power mode depending on the setup

If you watch the TPS 1 & 2 % readings separately you will see that they are at 100% before the 75% of the indicated angle. This is all in the software of the PCM. When you continue to push the APP when the TPS 1 & 2 readings are at the 100% even when the actual TPS reading is the same 70% as the APP then it will closed the throttle and most of the time go into reduced power mode.


It is all in the Engine and the Engine Diag Segments.

Again -->I will work with Bill at HPT to get them added for everyone. If HPT feels that this is all save then I would figure that they should have them added shortly

Hex Hacker

I was collecting them for testing. These were not all LS2 style T-bodies. They fit 2002 to 2013 cars and trucks. Most of them were pulled off of trucks before the TSB came out for replacing the TPS (DTC P2135).

My boy says I sent him to scrap 80 lbs of throttle bodies. I had 18 short skirt pistons that was in that tote to be scrapped. I guess I had a few more than 20.

aknovaman

iTrader: (7)

"I have it all figured out"..... Seriously?

gofastwclass

iTrader: (2)

What about the V6 pedals (think V6 F-Body cars) that would fit more swap vehicles than huge truck pedals? Do those still get ignored? I thought "Most" would include them.

I'm told some of the newer cable throttle body PCM's don't have the driver to communicate with the TAC and DBW setup, but don't remember a cutoff year or if the PN changed. Are you aware of this?

ncdino

I need some help guys, I recently purchased a 2000 corvette that has issues ie reduced power mode, no throttle response and a very loud noise from the TB when the ignition switch is turned on. I have replaced the ecm, tac module and tb( the noise coming from the tb was found to be three teeth sheared off the tb shaft gear in the wot area of the gear) My question is what could be causing these gear teeth to shear off. It seems the ecm does a system test each time the ign switch is turned on and the throttle momentarily goes to wot and back to near closed position.