Any idea on what size fuse for the main power?

I plan on pulling the switched 12v for both from the in dash fuse panel, with one of those fused "add a circuit" things. Any recommendations for fuse size and which circuit to plug into?

I have my wideband on one of them, if I recall its the "engine" circuit.

 

I don't know how much power those solenoids draw, but probably only a couple amps each. I would do a 15amp main, and a 3amp on the switches.

I used an add-a-circuit on the instrument panel fuse I think (top right), and it came with a 10amp fuse which is fine. The add-a-circuit will fuse the switches, so no need for individual ones. To flip a relay only takes about 0.33amps.

 

Okay so I'll prolly just add this stuff onto the wideband add-a-circuit.

And another question

Where is everyone getting RPM and TPS signals?

I found this, so TPS is one of those...

03 TRUCK TB
Pin - Wire Color - Function
A - YEL - TAC Motor Control 1
B - BLK/WHT - Low Reference
C - BRN - TAC Motor Control 2
D - BLK - Low Reference
E - LT BLU/BLK - 5 Volt Reference
F - PPL - TP Sensor 2 Signal
G - DK GRN - TP Sensor 1 Signal
H - GRY - 5 Volt Reference

And then for RPM i've heard grabbing it from the PCM wires is possible or behind the cluster. Behind the cluster sounds like a real pain to get to.

Some may find all this diagramming and planning a waste of time, but I find it easier going into this install knowing exactly where everything is going...

 

I got my RPM signal from behind the cluster. TPS would have to come from PCM/TB.

 

Did you pull the cluster? Thanks again for your help I really appreciate it.

 

I think so? Its not hard...

 

Just solder in a fuse holder on main ignition harness on the column. Cant screw it up there.

 

add-a-circuit is less invasive and easier , so I'll be sticking with that.

white wire behind the cluster for RPM - got it

 

I'm assuming it doesn't matter which TPS sensor wire (1 or 2) I plug into?

 

It does matter. What year is your truck?

There should be 3 wires, a 5V reference, a ground, and a TPS signal. If your truck is 03+ the TPS signal will be pin 24 on the GREEN PCM connector. RPM is pin 10 on the same green PCM connector.

If it's 99-02 it's the same 2 pin numbers but on the RED PCM connector. I found that here: 2004 Vortec PCM Pinouts ; 1999 to 2002 Vortec PCM Pinouts