98 GMC Twin Turbo with 12200411 PCM--- It's Alive

Performance modifications, tips & tricks

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96SWB
Posts: 2
Joined: Tue Jan 10, 2012 10:44 pm
Location: San Diego, CA

Post by 96SWB »

Excellent. Got the swap through Lextech. Anxious to install. Thanks all!

badbowtie
Posts: 5
Joined: Tue Oct 30, 2012 4:13 pm
Location: Indiana

Post by badbowtie »

I have a 99 k3500 454 4l80E 4x4 truck
Has anything ever been figured out for 4x4 If I read all these right 4 high works great and 4 low will not shift correct?
Also I have seen on hp tuners 02 express tune I have I see they have the performance tune. So can the tow haul button be hooked up for the swap.

Lextech
Posts: 964
Joined: Tue Mar 07, 2006 7:27 pm
Location: Oak Forest Illinois,U.S.A.

Post by Lextech »

4lo shifting was figured out ages ago. Tow/Haul mode (Performance Mode) can be enabled. Our GMT400 trucks don't have a BCM to turn on the Tow/Haul light. You would need to give the PCM pin C1-71 a momentary ground to enable/disable the function. When the key is turned off the mode is cancelled.

Jeff

kag96
Posts: 238
Joined: Fri Aug 24, 2007 8:36 am
Location: Northern Virginia

Problems with shifting!

Post by kag96 »

OK, this has been a long time coming. My Tahoe has been down for almost three years now. The last two winters have been mild to say the least, and the previous was surrounded by family tragedy. I NEED my "hoe" back. Here is the story....
I tore down the front clip and restored the panels.
Installed a GMPP HT383E
Marine Intake manifold
0411 ECM with Blackbear tune
Hydroboost installed
Freshened the steering components
Deleted "unnecessary" components and wiring (EGR,EVAP, Rear O2)

Everything was done and functions EXCEPT for two issues. The first is minor (comparatively), power steering is not functioning however Hydroboost seems to be. The second is that when id Drive, it does not change out of first automatically. However, I can manually shift through gears on the column. Additionally it acts as if the neutral safety switch is malfunctioning, sometimes it will not allow me to change out of Park as though I am not depressing the brake pedal. Other times I have to start the vehicle in Neutral and Then change gears.

I have a new Neutral Safety Switch
On circuit 771, Transmission Range Switch Signal A, Connector C1, Pin 32 I get 2.2-2.6Ω
On circuit 772, Transmission Range Switch Signal B, Connector C1, Pin 72 I get 2.2-2.6Ω
On circuit 773, Transmission Range Switch Signal C, Connector C2, Pin 62 I get 2.2kΩ
On circuit 776, Transmission Range Switch Signal P, Connector C1, Pin 34 I get 2.2kΩ

These are all measurements with the engine off and at rest (obviously)
The Wiring diagram I have is from year 2009, marked as revision #3. I don't know if it has been amended since. Any assistance would be greatly appreciated. Thanks!

Lextech
Posts: 964
Joined: Tue Mar 07, 2006 7:27 pm
Location: Oak Forest Illinois,U.S.A.

Post by Lextech »

There are no mistakes in the wiring file. I you think the range switch is not acting right--(Feeding back or Shorted) Unplug the lower connector of the range switch and also remove the 4 pins from the PCM. The trans will function without that input. Also, Remove the pin from the PCM for the front axle input to the PCM. Maybe---It is telling the PCM that it is in 4low and that is messing with the upshift. That is all I can think of.

Jeff

kag96
Posts: 238
Joined: Fri Aug 24, 2007 8:36 am
Location: Northern Virginia

Post by kag96 »

Lextech wrote:There are no mistakes in the wiring file. I you think the range switch is not acting right--(Feeding back or Shorted) Unplug the lower connector of the range switch and also remove the 4 pins from the PCM. The trans will function without that input. Also, Remove the pin from the PCM for the front axle input to the PCM. Maybe---It is telling the PCM that it is in 4low and that is messing with the upshift. That is all I can think of.

Jeff
Unplug the lower connector? It's been a while since I've been at that point of the harness, but are you referring to the round 4l60 trans' connector? Isn't that where the source signals derived from for the previously mentioned pins?

Lextech
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Joined: Tue Mar 07, 2006 7:27 pm
Location: Oak Forest Illinois,U.S.A.

Post by Lextech »

kag96 wrote:Unplug the lower connector? It's been a while since I've been at that point of the harness, but are you referring to the round 4l60 trans' connector? Isn't that where the source signals derived from for the previously mentioned pins?
The lower (4 pin) connector of the big, black switch on the drivers side of the trans.

kag96
Posts: 238
Joined: Fri Aug 24, 2007 8:36 am
Location: Northern Virginia

Post by kag96 »

The smaller of the two connectors on the neutral safety switch? If I remember correctly, the other connector is a 6 or 8 pin grey connector with a blue gasket. Right?

Hog
Posts: 5025
Joined: Tue Dec 11, 2001 4:00 pm
Location: 1997 Chev ECSB L31 350 1997 GMC Sierra SLE RCSB, Ontario

Post by Hog »

Then they wrote a book,


I hope your pinouts arent being published Jeff.

http://forum.efilive.com/showthread.php ... Throughout

Our little "project" sure has come a long way. Thanks Lextech of PPE and Airdeano tuner/E Engineer of S&P.

peace\
Hog
Last edited by Hog on Wed Aug 07, 2013 12:32 pm, edited 1 time in total.

CrazyHoe
Posts: 6228
Joined: Tue Feb 19, 2008 8:30 am
Location: Mtl; '98 2dr4x4 Tahoe, L31,Hookers Long T, 0411,EFIlive, 4L80-E,dual 3",marine int+inj

Post by CrazyHoe »

That<s pretty awsome

Lextech
Posts: 964
Joined: Tue Mar 07, 2006 7:27 pm
Location: Oak Forest Illinois,U.S.A.

Post by Lextech »

There are no wiring files published. Mike Noonan (The owner of EFIConnection) and I have been friends for several years. He contacted me about 14 months ago to let me know he was in the beginning stages of a fuel injection book. He said he thought my truck project was in the spirit and theme of the book and asked if I would like to have it listed as one of the project vehicles. He caught me off guard with that question. I said "Sure". I was very excited about the possibility of the truck being in a book. I supplied Mike with as much info as I could think of and he wrote the section about it. Mike is a VERY sharp guy and has a LOT of knowledge of GM fuel injection. I have only seen the rough draft of my truck. I am anxious to get my copy. Hopefully any day now.

Thanks Mike.
Jeff

Hog
Posts: 5025
Joined: Tue Dec 11, 2001 4:00 pm
Location: 1997 Chev ECSB L31 350 1997 GMC Sierra SLE RCSB, Ontario

Post by Hog »

Good to know that you are in the know, thanks Jeff.

PS I should have stated "I hope the schematics weren't being published WITHOUT YOUR KNOWLEDGE". Obvioulsy its your work and you can do with it what you wish.
I hate it when people rip off other peoples work, it's all about getting those hydrocarbons to burn.

peace
Hog

Lextech
Posts: 964
Joined: Tue Mar 07, 2006 7:27 pm
Location: Oak Forest Illinois,U.S.A.

Post by Lextech »

Hog wrote: "I hope the schematics weren't being published WITHOUT YOUR KNOWLEDGE".
I'm sure that never entered his mind. Mike is a good guy. I don't "think" there is any wiring discussed at all in the book.

Jeff

S10Wildside
Posts: 172
Joined: Tue Mar 27, 2007 11:24 am

Post by S10Wildside »

Hi Guys

The book idea came at somewhat of a breaking point. There are only so many hours in a work day. When I recognized too much time was going into answering the same questions, it seemed appropriate to share answers to these common questions in one place. The release of this book should help me focus more on the customers of EFI Connection, LLC (getting paid orders out the door) and new product development. I have some very capable guys working in the shop and even they deserve my attention to move forward in new directions.

I was introduced to the idea of the 12200411 PCM back in the fall of 2006 when a customer asked for a harness build for his Ram Jet 350 engine. I built his harness and then one for the 1989 TPI engine in the workshop. Everything worked out great and then I moved on to the 24x product line. I was unaware of the efforts in this forum for some time, but you guys have really paved the way (in a significant way) for upgrading the 1996-newer trucks with the 12200411 PCM. Jeff's truck is such a fantastic example of the 12200411 PCM conversion that it fit perfectly into the scope of this book.

The world is a big place and I'm sure there are others who hold great knowledge on this topic. Props to all who have helped others make use of this technology!

Mike

S10Wildside
Posts: 172
Joined: Tue Mar 27, 2007 11:24 am

Post by S10Wildside »

Lextech wrote:I don't "think" there is any wiring discussed at all in the book.

Jeff
I did draw schematics for the book...(using Windows Paint!). I also made clear in the intro that the book is not about how to build your own wire harness. Where appropriate, I drew schematics to help with chapter topics.

Also keep in mind that there are constraints to writing a book...like number of photos (about 500) and page count (about 140). There's only so much content that will fit. There are books about tuning (see Greg Banish's work) and factory schematics for DIY harness building.

Whipped383
Posts: 2104
Joined: Mon Mar 01, 2010 9:12 pm
Location: Salt Lake, 97K1500,ECSB, 383,Whipple,0411,Marine, 03K2500,CCSB,8.1&Allison, Whipple in progress

Post by Whipped383 »

Are you selling the books mike? Id rather place an order with you than amazon if you are.

S10Wildside
Posts: 172
Joined: Tue Mar 27, 2007 11:24 am

Post by S10Wildside »

Whipped383 wrote:Are you selling the books mike? Id rather place an order with you than amazon if you are.
Yes. The book is available at http://www.eficonnection.com/eficonnect ... temId=1240.

Hog
Posts: 5025
Joined: Tue Dec 11, 2001 4:00 pm
Location: 1997 Chev ECSB L31 350 1997 GMC Sierra SLE RCSB, Ontario

Post by Hog »

S10Wildside wrote:Hi Guys

The book idea came at somewhat of a breaking point. There are only so many hours in a work day. When I recognized too much time was going into answering the same questions, it seemed appropriate to share answers to these common questions in one place. The release of this book should help me focus more on the customers of EFI Connection, LLC (getting paid orders out the door) and new product development. I have some very capable guys working in the shop and even they deserve my attention to move forward in new directions.

I was introduced to the idea of the 12200411 PCM back in the fall of 2006 when a customer asked for a harness build for his Ram Jet 350 engine. I built his harness and then one for the 1989 TPI engine in the workshop. Everything worked out great and then I moved on to the 24x product line. I was unaware of the efforts in this forum for some time, but you guys have really paved the way (in a significant way) for upgrading the 1996-newer trucks with the 12200411 PCM. Jeff's truck is such a fantastic example of the 12200411 PCM conversion that it fit perfectly into the scope of this book.

The world is a big place and I'm sure there are others who hold great knowledge on this topic. Props to all who have helped others make use of this technology!

Mike
I remember when you did a Ramjet intake on an L31 engine, I think it was installed in a Syclone without the AWD hooked up, maybe? I remember you posting the dyno graph. That dyno graph has been a staple in my Photobucket account.
Oh wait, maybe it was a Ramjet 350 crate and you took away the MEFI and installed a 512kb PCM. I remember you got way better numbers with you own tuning.
ANd here it is.
Image

Mike, I remember your surprise when you came over here to PPE and discovered that GM had a 24x reluctor in the very rare GEV VI L21, and the one L21 engine that didnt sell on its 1st pass on Ebay. I think you ended up buying afterwards.
That thread was dated May 04, 2008, and Lextech posts that he has been working on a 24x reluctor COP/CNP project for a while.
I assume you 2 were collaborating?

Here is the thread from May 04, 2008
http://www.pacificp.com/forum/viewtopic ... hlight=l21

It is apparent that you had been at work for a while.

Here is a post dated Jul 21, 2005. I asked some questions, made some observations, and used this thread to keep track of info that could be used for 0411 PCM swapping. As you can see it didnt look promising at points, but I kept thinking, if GM uses a Vortec 350 in the 1996-97 GMT 400 trucks, and the 1998-00 GMT 400'like vehicles and used 2 different versions of the "blackbox" PCM to control the same L31 engine, then for MY2001-2003 GM used a dual 80 pin connectored PCM to control the exact same engine that aside from some possible sensor changes, there has to be a way to get this 512kb PCM retofitted into the 1996-2000 GMT 400 trucks/SUV's.
http://www.pacificp.com/forum/viewtopic ... 11&start=0

The 0411 swap was needed in the marine intake world from day 1. The very 1st "documented" Mercruiser Marine Intake retrofit was by a guy with teh username RCFast. He got his marine intake installed with a nice lumpy cam, and then went for a rip and discovered his part was being shut down at 5600rpm, he was hitting the stock blackbox 5600rpm rev limit. No problem, he reflashed with a 7000 rpm rev limit. Went for another drive but even with 7000rpm as a rev limit in the calibration, the engine would shut down at approx 5900rpm. I took on this mission to find out what was going on. After looking into the calibration in hex and speaking with most of old school and some new school PCM recalibrators it was discovered the "blackbox" PCM has a "hard" revlimit of 6000rpm. Akin to the hard limit of the LT1 PCM's that peeter out at approx 7300-7400rpm. The pulsewidths simply shut own to "0".

Jul 06, 2005 Actual post from RCFast
http://www.pacificp.com/forum/viewtopic ... sc&start=0

Rev limiter work from Aug 11, 2005
http://www.pacificp.com/forum/viewtopic ... ight=#7902


Jul 13, 2005 Even got Ed Wright of Fastchip in on the fun, he "thought" he could set a 12,400 rec limit, but in the end was defeated l;ike the rest of us.
http://www.pacificp.com/forum/viewtopic ... ight=#6679

Jul 13, 2005 And another innovator, Lyndon Wester of Westers's Garage.
http://www.pacificp.com/forum/viewtopic ... ight=#6552

There is a guy with the username Airdeano. He is/was an Engineer/PCM calibrator at S&P. He did the dyno tuning that was done for the development/certification of the V-Maxx spacer for the Vortec 4.3/5.0/5.7. This device simply adds about an inch thick aluminum spacer between the upper plastic plenum and the lower aluminum intake manifold. It increases plenum volume and is said to increase both horsepower and torque. The same company developed a handheld device that would reflash the"black box" with his predevopled tune. Gains in power and torque were the largest of the handheld world for the L30/31 305/350 applications.

We discussed the possibility of using the 411 PCM (he referred to the 411 as the 8.1 box) retrofitted into theGMT 400 trucks. We discussed this via PM over at FSC(full size chev) truck forums(the enemy lol). During these exchanges he e-mailed me the necessary pinouts. That email is dated April 1st,2006 and was labelled "Pauly's Pinouts". This email's attachments were shared, and others compiled. It was discovered by Lextech that there were indeed differences between the 1996 and 1997 PCM/truck that necessitated seperate wiring files for both the1996 "blackbox" and the 1997 "blackbox" as well as the 1998-2000 "blackboxes" which were equipped with VATS.

Another development was when Tunercats OBD2 was released, there is more to this story, but I must break for now. I look forward to getting a copy of the book. Thanks go out to you Mike and I would like to thank you and the others at EFIConnection for all your hard work. It's one thing to have an idea, but another to take that idea and make a career out of it.

I'll probably send in an order tom morn for the book and a set of 411 PCM connectors.

peace
Hog

Goldhawg
Posts: 24
Joined: Sat Feb 23, 2013 12:24 pm
Location: Ohio

Post by Goldhawg »

For efan control, if I read the excel spreadsheet correctly, both pin locations (C2 33 DK GRN from C4-7--HS Fan #2 and C1 42 DK BLU from C4-9 for Fan #1) have wires from the original harness. Do I have to find the end of these wires and extend them to the fans, or do I just tape off the original harness wires and run two new wires from the C2 33 & C1 42 directly to my fans?

Lextech
Posts: 964
Joined: Tue Mar 07, 2006 7:27 pm
Location: Oak Forest Illinois,U.S.A.

Post by Lextech »

Goldhawg wrote:Do I have to find the end of these wires and extend them to the fans, or do I just tape off the original harness wires and run two new wires from the C2 33 & C1 42 directly to my fans?
I have never seen a GMT400 truck with factory dual electric fans. A very few had a single electric auxiliary fan. If your truck has the factory auxiliary fan and you just want to use it as such---then the wiring is already there and you would repin at the PCM accordingly. If your truck doesn't have any factory installed electric fans and you want to add one or two, then you need to add all of the wiring and relays for the setup.

Jeff

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