View Full Version : 2001 Buick Century

M Bell
08-19-2008, 10:52 AM
I have been working with hho for about 2 months. I have an extender on my o2 sensor. I have a gen. that is producing approx. 1 lpm. I have seen returns of about 4 to 5 mpg increase. I recently added a maf/map but am having trouble with the signal to the ECU. I have the wiring diagrams for the car. I have a 12 volt and ground imput into the maf sensor. I have a 5 volt wire that is supposed to be the signal. When I seriesed the maf/map with the signal wire the adjustment pots were adjusting the voltage to the maf and not the ECU. I swapped the wire leads but to the same results. Does anyone have any ideas?

08-22-2008, 12:50 AM
The 5 volt wire you say is the signal wire.....is it 5 volt constant?
Your signal wire should vary in voltage depending on the rpm of the engine. at Idle it should be a volt or two and as you rev the rpm's up the voltage should climb. 5 volts should be max voltage I would think.

Could you have the wrong wire?

Is there more than 3 wires going to it?

On my wiring diagram there were 2 wires that were labeled similarly and the descriptions were vague so I had to strip a little insulation on the suspect wires and test them until I found the right one.



M Bell
08-22-2008, 06:24 PM
I just checked today with the correct type of meter and found that the signal is varying the frequency. It is changing from about 2.5 hertz at idle to 4.5 at 2000rpm. I am going to have to try and research how I can make a unit to modify this. I dont know of anyone else that has developed a unit for it.

09-13-2008, 12:36 AM
The best way to find the proper wire is by back probing with a straight pin then use a mutimeter in series with a low voltage test light to find which wire is the fluctuating signal.
Even better yet see if there is a haynes repair manual for your vehicle it will usually tell you exactly which wire is which.
The 2000 Buick that I am experiencing with has a variable frequency signal and will not accept these enhancers as they are designed to be used only with voltage signaled frequency back to the ECU

09-13-2008, 01:30 AM
The yellow wire looks like signal wire.
The pink wire is ignition voltage.
The black/white is ground.

Hope that helps.