94 Lifted Silverado 6.0/4L80e swap Build

[bobbylog]

First, when the truck has been driven for a while and is up to temperature, i come to a stop sign and it will want to keep going and if i press the brake to try to stop it it will act like its going to stall out. So I have to put it in neutral. But when its cold i can stop and it will idle just fine with me on the brake.

Did you wire the brake switch signal to the pcm...? The PCM need a 12 v when the brake are not being applied (the opposite of a standard brake light switch) This signal control the torque converter lockup.

[HPICamaroSS]

Did you wire the brake switch signal to the pcm...? The PCM need a 12 v when the brake are not being applied (the opposite of a standard brake light switch) This signal control the torque converter lockup.

How do I do that? I'm sure thats the problem because I havent done that lol

[bobbylog]

How do I do that? I'm sure thats the problem because I havent done that lol

I have never do that to but from what I've read you need a switch like this.
http://www.ebay.com/itm/TCC-BRAKE-SW...item27c42fbcc4
http://secure.ultracart.com/catalog/...f/KIT-1002.pdf
I've read that you can use a relay to but in my case I will just buy the switch.
Your nelsons harness is supposed to have 1 or 2 wire ready to hook to the switch.
Edit:

For automatics with lock up converter, the PCM needs signal when brake pedal is pressed. However, the signal needed is opposite how you're brake lights work. The PCM wants 12v+ constant on this wire when brake IS NOT pressed, and OPEN Circuit when the brake IS pressed. If you vehicle was equipped with a lockup trans to begin with, you probably already have the proper normally closed switch mounted by your brake light switch. If you do not, you can use a relay to perform the same thing. On most relays, there are 5 terminals, 2 of them turn the relay ON when provided ground/power. There are then a normally open leg and a normally closed leg on the relay and a supply. By feeding 12v+ on the supply leg, and hooking the Brake Switch Signal wire to the normally closed leg, you will now have the correct signal for the PCM. When the brake is pressed, 12v+ flows to brake lights, tap into this wire, and run it to the relay to turn the relay on. This will cause the normally closed leg to become open, thus turning OFF the 12v+ signal to the PCM. When you release the brake pedal, the relay will turn OFF, and then feed 12v+ to the PCM.

From Lt1swap.com http://lt1swap.com/wiringharness.htm
So you are supposed to already have a brake switch like this.

[92 6.0]

How do I do that? I'm sure thats the problem because I havent done that lol

Its real easy. Just find the brake switch in your truck. Its on the pedal up under the dash a lillte bit. And then look for the purple wire and splice the one from your swap harness to it and your done.

[HPICamaroSS]

Its real easy. Just find the brake switch in your truck. Its on the pedal up under the dash a lillte bit. And then look for the purple wire and splice the one from your swap harness to it and your done.

Do you know which wire I have to splice it into on Nelsons harness? Because their harness is a 4 wire hookup, and that doesn't include a wire for the brake

[bobbylog]

Do you know which wire I have to splice it into on Nelsons harness? Because their harness is a 4 wire hookup, and that doesn't include a wire for the brake

This wire is supposed to be with the dash group speedometer,tach...Also did you wire your park neutral switch? The pcm need to know when you are in gears..

[RedHeartbeat]

Sounds like you need a resistor inline with the tach module. There is one year of pcm that has a very weak signal to the tach. Do you know what year your tune is from? Is it dbw?

[HPICamaroSS]

Sounds like you need a resistor inline with the tach module. There is one year of pcm that has a very weak signal to the tach. Do you know what year your tune is from? Is it dbw?

I have no idea what year the pcm was but I just sent it back to nelson and they already have a new one for me on the way. They changed the pulse cycle to see if that helps. Once I get it I will let you know. Hopefully its right because if its not then I will have to send it back again, and have them change it back to where it originally was, then try putting that resistor in. I want to say that tune was from a 2002 because I recall them saying those were the easiest to tune. I know it was a 0411 ecm.

[Wagonbacker9]

I have no idea what year the pcm was but I just sent it back to nelson and they already have a new one for me on the way. They changed the pulse cycle to see if that helps. Once I get it I will let you know. Hopefully its right because if its not then I will have to send it back again, and have them change it back to where it originally was, then try putting that resistor in. I want to say that tune was from a 2002 because I recall them saying those were the easiest to tune. I know it was a 0411 ecm.

Computers used were 09354896 from 99-00, and 12200411 from 01-02

Im pretty sure the tach wire (on the obs) is the white wire. Unless I have the wrong white wire

I meant that you were possibly supplying the tach with vehicle speed info.

[HPICamaroSS]

Got my "retune" back from nelson which was basically them just adjusting the tach so i didn't have to put a resistor in it. Seems ALOT closer now. Once I get the scan tool I can hookup to confirm RPMS. Thanks to Erica and Ray at Nelson Performance.