you do realize that capacitors do nothing right? for them to do anything you would need a massive capacitor bank and then it would be drained after one bass hit anyway. I also have the amp dyno for my alt and you can't get a cheap aftermarket alt for these cars.
to each their own... but you do realize your most likely wrong on that one... This is stated right from Cruthfield and hand on results.
Q: What's a capacitor?
A: A capacitor, or cap, is an electronic component that can take up, store, and discharge electrical energy. Because they can do all that quickly, capacitors are used to filter or buffer any sudden changes in a circuit's voltage, smoothing the ensuing signal.
Q: What's a capacitor used for?
A: In car audio, large outboard capacitors, sometimes called stiffening caps, are used to prevent lights from dimming when loud bass notes play. They accomplish this by supplying the amplifier with a quick jolt of power.
Q :HOW DOES A CAPACITOR WORK?
A: Stiffing capacitors store electricity, which they can discharge very quickly unlike the vehicles battery and alternator. They give your amplifier quick jolts of power when the bass hits to cover the amount of current it requires for musical transients. This ensures the amplifiers in your car are properly supplied and working at peak performance.
In regards to the FAN SPEED DECREASING at idle: Check: CABIN AIR FILTER - if dirty would have decrease in CFM because of extra air resistance passing over a blocker filter... FAN RESISTOR, AND maybe FAN PIN VOLTAGE.. Also I still believe 14.8 PLUS volts is a little too high.. H/K prefers it closer to 14.0V-14.3V... Charging at almost 15 volts all the time will shorten your battery life also.
But if the FAN SPEED DOES NOT INCREASE OR DECREASE with the switch, it could be the RESISTOR .... basically it would be one speed no matter what number you selected if that was bad (on/off)