PDA

View Full Version : re Homemade Boost fooler - is the Ground wire needed?



MTTwister
04-21-2004, 11:31
I have mine wired-up and ready to install. I was wondering tho': Can I just get by with the variable resistor spliced into the 'green' wire?

Or, do I really need to tap the other leg ( for the full 10k) into the middle / ground wire?

Seems to me that just varying the resistance across the "green's" would be enough - BWDIK. Thanks

gmctd
04-21-2004, 12:56
It's all about current and voltage, MT.

PCM is looking for voltage input from Boost sensor, representing pressure. With pot across B to A, the wiper can tap off any percentage of the voltage between B and A, 0 to 100%.

Connected as a rheostat between B and the PCM would vary the current flowing into the PCM input, also resulting in a voltage change, but insignificant compared to the output range from the potentiometer.

Ground the CCW end of the pot to A, CW end to B, wiper to Boost Signal wire that was on B

MTTwister
04-21-2004, 12:58
gmctd - Got Ya, Thanks! BTW - it's linear, but gotcha.

[ 04-21-2004, 01:53 PM: Message edited by: MTTwister ]