DBW and Computer Issues

[rmvlt1100]

I am still having issues with my DBW setup. I was able to get the pedal to operate but still having idling issues and operational issues with the DBW setup.

I found the paper work for my 5.3L engine, PCM, TAC box and DBW pedal. The PCM and the engine are from a 2005 Silverado and the TAC Box and the DBW pedal are from a 2004 Silverado.

I have read through here that the mixing of the different years for these parts can cause issues with the operations of the DBW working properly and/or at all. If I have to replace the TAC box and the pedal assembly is it best to contact the dealer for new ones or does any one here know were would be the best place to get them? Any help and/or comments would be great.

Have a great day and thanks for any info;
Robert

[68GMCCustom]

I'm finding that having different year components can cause issues. It seems somewhere not too long after the LS series came out...GM started changing component wiring/harness wiring/schematics every few years...then every other year.

[clinebarger]

Usually if the TAC & Pedal are from the same year....It works.
Any codes?
If in fact you do have a mismatch issue.....I would have the PCM reflashed with a 04 VIN before buying & changing the TAC & pedal.

[rmvlt1100]

Originally Posted by clinebarger

Usually if the TAC & Pedal are from the same year....It works.
Any codes?
If in fact you do have a mismatch issue.....I would have the PCM reflashed with a 04 VIN before buying & changing the TAC & pedal.

Thanks for the info I will call the place that programmed my computer to see if they could try this fix.

Thanks again,
Robert

[rmvlt1100]

Originally Posted by 68GMCCustom

I'm finding that having different year components can cause issues. It seems somewhere not too long after the LS series came out...GM started changing component wiring/harness wiring/schematics every few years...then every other year.

Thanks for the info I may just invest in a complete new system.

Robert

[BR3W CITY]

is there any throttle response at all, and as cline mentioned, any codes?
you said it operates, but what exactly is it "doing"

[rmvlt1100]

Originally Posted by BR3W CITY

is there any throttle response at all, and as cline mentioned, any codes?
you said it operates, but what exactly is it "doing"

The throttle does work some what. When you press down even a little it will go to wide open throttle. When you let off on the throttle the rpms will drop to guessing around 1700, then they will drop again to a normal idle. After a couple of minutes the idle will drop to almost a stall.

The check engine light is on but right now I don't have a code reader but plan on picking one up today after work.

Thanks for the response and any help would be great.

I am new to this LS type of engine and slowly starting to figure things out with help.

[faribran]

i like clinebarger's idea...... hang in there son, you will figure it out.

[rmvlt1100]

Originally Posted by faribran

i like clinebarger's idea...... hang in there son, you will figure it out.

Thanks Faribran, It's just fustrating right now. I have some calls into the tuner to see if he could do his magic. There are other things to do with the truck so that may help.

[rmvlt1100]

Well I read the computer and I showed 6 codes.

Here is the list;

P0068 x 2
Throttle Position Sensor Inconsistent with the Mass Air Flow Sensor.

P0107 x 2
Manifold Absolute Pressure/Barometric Pressure Circuit Low Input.

The MAP sensor is new so I will check the wiring for any issues.


P0120
Throttle/Pedal Position Sensor/Switch 'A' Circuit.

P0220
Throttle/Pedal Position Sensor/Switch 'B' Circuit Malfunction.

U0107
Lost Communication With Throttle Actuator Control Module.

If any one has any ideas please let me know.

Have a good weekend,
Robert

[BR3W CITY]

the 220 and 120 are tac pedal failure problems....check for a purple wire out of the harness, if its loose you can ground it. Otherwise it could still mean a component mis-match.

I'd also check the wires going to the TB.

After it rev's and then it comes close to dying, can you try to keep some foot on it to keep it alive, or does the pedal stop responding?

[clinebarger]

The yellow wire at the throttle body is bad about breaking, & can set all those codes but U0107. Lightly pull on all wires if one stretches....Its broke.

U0107 is usually a bad ground or Ignition feed to the TAC module...Pin #7 Pink wire ignition power, Pin #15 Black wire ground.

[rmvlt1100]

Originally Posted by BR3W CITY

the 220 and 120 are tac pedal failure problems....check for a purple wire out of the harness, if its loose you can ground it. Otherwise it could still mean a component mis-match.


I'd also check the wires going to the TB.

After it rev's and then it comes close to dying, can you try to keep some foot on it to keep it alive, or does the pedal stop responding?

If it has a purple wire do I just ground the wire out to metal? (Sorry if that sounds like a stupid question.)


The pedal still responds but it is like a hair trigger, the rpms shoot right back up. Its hard to get a steady smooth idle by feathering the pedal.

Also thanks for the help.

Robert

[rmvlt1100]

Originally Posted by clinebarger

The yellow wire at the throttle body is bad about breaking, & can set all those codes but U0107. Lightly pull on all wires if one stretches....Its broke.

U0107 is usually a bad ground or Ignition feed to the TAC module...Pin #7 Pink wire ignition power, Pin #15 Black wire ground.

Clinebarger,

Thanks for the info I will check the wires to the thorttle body.
Any info and help at this point is great.

Robert

[osaltyone]

Did you figure the throttle/pedal issue out?

[rmvlt1100]

Originally Posted by osaltyone

Did you figure the throttle/pedal issue out?

Yes after a bunch of phone calls to different companies. One call was to Speartech and they check the part numbers for my PCM and the TAC box and to see if they will work with each other and the will. So I started triple checking the wires and did what GM mechanics call the shake test and found a couple of loose grounds that were bolted to the back of the engine block. Now the system is working good. Still having some idle issues but it's a lot better. Thanks for asking.

Have a good day,
Robert
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[rmvlt1100]

Originally Posted by osaltyone

Did you figure the throttle/pedal issue out?

After I originally wrote the response I checked out your build. The truck looks great. That red is a nice color. I think mine is going red just with a flat clear. With your DBW Speartech helped me out. They said that for mine engine being a 2005 the TAC box from a 2004 will work with mine. Good luck with the LS upgrade.

Robert
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Posted via Mobile Device

[osaltyone]

Originally Posted by rmvlt1100

After I originally wrote the response I checked out your build. The truck looks great. That red is a nice color. I think mine is going red just with a flat clear. With your DBW Speartech helped me out. They said that for mine engine being a 2005 the TAC box from a 2004 will work with mine. Good luck with the LS upgrade.

Robert
Posted via Mobile Device
Posted via Mobile Device

Thanks! I wish I could get a good painter to match the color. Everyone is always off a shade and it shows on touch ups. I will try to do the shake test and see what I find. Have to take it to the exhaust shop first. Running it straight manifolds is making my wife and neighbors not happy...