On Friday, October 12, 2012 7:59:52 AM UTC-5, Existential Angst wrote:
Awl --



Would seem like a no-brainer, but goddamm, it shore has me beat!



Yeah, I know, pull the fuse!! Yeah, I know, the fuse labeled

"alternator".....



But when I did that, the alternator light or battery lite would not come on.

AND, iirc, I DID check the voltage at the battery, to see if it went down

to 12, or was up at the ususal 13-14, and indeed, it stayed at 13-14,

indicating a working alternator.



And the engine compartment is so g-d crowded/complicated, I can hardly tell

a wire from a hydraulic line, so it's not easy to even find the right wire.

I figger at 100 A, the wire would have to be perty thick....



The reason for disconnecting the alternator is this:

On an old mazda 929S, the alternator went -- and I could StoG that my mpg

jumped by 15%.... would like to re-examine this phenom with my ScanGauge,

to see if it is real.



If this is indeed a true phenom, I could wangle myself a bit of a hybrid by

just keeping a spare batt in the car, and switch in the alternator when the

first batt dies. But basically try to do all the batt. charging at home.



Altho, there proly is no free lunch: I'll proly use my gas savings to buy a

new battery every year?? LOL

But the actual tradeoff would be inneresting to see.

Many cars have a full-throttle alternator cutout circuit.
I would try to determine if your Mazda came with such, and try to insert manual control in that circuit. There may be other conditions that trigger alternator cutout from ECM control. You may be able to fool the ECM into seeing those conditions.