How does resistor mod increase boost?

[Dietoremain]

Call me immature but I want to put one on a switch just so i can smoke people out... lol. dont want to abuse my ICP too much!

[Dudenhymer]

Yes you cut the Blue/Green wire and put a resistor inline. From what I've read (as I'm new to this) this works opposite and better then just connecting the resistor btw the two terminals. Best to use anything from 10K to 22K if using this method.
The ICP sensor resistance increases with intake manifold pressure. The PCM reads the voltage drop on the Blue/Green ICP return line (Higher resistance = higher voltage drop) It compares this voltage drop to the drop across the reference resistance (Grey/Red 6KOHM). PCM uses the difference between these two voltage drops to determine how much fuel to add to the mixture. So putting a resistor inline with the ICP return (Blue/Green) increases this difference.
If you do it the easy way and just hook the resistor between the ICP return and the reference lines then you are putting the resistor in parallel with the reference resistance thus decreasing total resistance.
This is all based on what I've read over the past couple of nights. I wish I could see the circuit to better understand exactly what is going on.

[RRonning1984]

The switch is a good idea. Running the numerically lower ones like 2.2K and 1K can blow the diaphragm in the ICP.

[Dudenhymer]

Originally Posted by RRonning1984

The switch is a good idea. Running the numerically lower ones like 2.2K and 1K can blow the diaphragm in the ICP.

If hooked in parallel between the two terminals right?? This is the part I'm not understanding. What the effect on the circuit is if hooked up in parallel. It doesn't seem right doing it this way. Hooking it in series makes sense but hooking the resistor between two signal lines as I understand them to be is probably the source of crappy idle, high end power dropoff and screwed up ICPs.
This may have already been covered and I just haven't found it yet.

[v8fla]

thanks for the answer,i agree a schematic would make it easier to grasp.

[CRAZY_CANUCK]

look a little towards this post as well. Sorting through all the cr@p!! Please help new Diesel owner!

[RRonning1984]

This is from my other thread listed above.

Originally Posted by RRonning1984

The blue butt connecters are my way of tapping the wires to the ICP.

The grey wires I have coming out the end of the butt connectors are the ones running to the switch. Just to be clear do not cut the ICP wires. Just splice/tap in to them. You can see I have my 10K plugged right in to the ICP as I run it full time. I have a 2.2K on the switch!

[Dudenhymer]

This would be the parallel method I'm referring to. The series method would have you cutting the ICP return wire (Blue/Green) and placing a resistor in line there.

[Dudenhymer]

RRonning it looks like you've got a 10K in parallel with the 2.2K which is on a switch which is in parallel with the reference resistance (6K). Putting the 10K in alone drops your reference voltage down from 6K to 3.75K. Flipping on the 2.2K switch brings the referenc voltage down to 1.39K. Each step down creates a greater difference in voltage drop between the ICP voltage drop and the reference voltage drop. Hence the added power of the 2.2K

1/X = 1/6K + 1/10K + 1/2.2K

[RRonning1984]

Originally Posted by Dudenhymer

RRonning it looks like you've got a 10K in parallel with the 2.2K which is on a switch which is in parallel with the reference resistance (6K). Putting the 10K in alone drops your reference voltage down from 6K to 3.75K. Flipping on the 2.2K switch brings the referenc voltage down to 1.39K. Each step down creates a greater difference in voltage drop between the ICP voltage drop and the reference voltage drop. Hence the added power of the 2.2K

1/X = 1/6K + 1/10K + 1/2.2K

Ya, something like that.