A capacitor does not generate its own power, it gets power from another source (the alternator in a car). It is a passive electrical device. Yes it will maintain the electrical energy and smooth out the power but the underlying cause is the alternator not suppling enough current. The capacitor does not add current to the circuit and that is what is needed to supply enough current to the amp which is now the most demanding device in the circuit leaving all other devices (lights, ecu) to struggle for what they need. Its hunger games out there!!

 

The amplifier also has capacitors in it. These also get charged by the car before the music starts. The issue here isn't charging the capacitors. The issue is the amp draining the power for the speakers. A big enough capacitor near the battery will prevent the car from browning out. Bigger capacitors in the amp would only prevent the amp from browning out. Capacitors only takes seconds to charge and can supply power for tiny millisecond to second outages, which I believe can be a problem here. I'm not saying a bigger alternator or a bigger battery wouldn't help. They will, but so will a capacitor.

 

Yes a capacitor adds something else for the already struggling alternator to now charge. You just added an amp (with capacitors in it) and MOSFET's, diodes and other power hungry devices in it. Yes the amp drains the already limited current in the circuit provided by the alternator.

Car needs 100 amps normally and alternator supplies 120. You now need 140 amps to power everything the car already needed to power plus the amp. Now you add a passive device to the equation (capacitor) and the alternator needs to supply power on top of the already struggling system to charge the capacitor. Issue was not fixed, more current is still needed.

The capacitor will help keep the lights from flickering yes and help the ECU but it will also act as a buffer to the amplifier getting the power it needs. I think OP's money would be better spent on a grounding upgrade and larger alternator. The key issue is there is not enough current in the curcuit to power the needs of the car and the amp. What is charging the capacitor, the alternator. It is going to work harder to keep it charged and the capacitor will just add strain.

 

It all depends on what the problem is that none of us know. However OP can certainly use a simple online calculator to figure the RMS (and peak) they need for the amp/speakers and see if their alternator and battery can handle it. An amp can still draw more than supplied though for short instances even with these upgrades.

 

Well, I found the problem. Whilst installing the stereo, I also installed a backup camera. My car is a 5 speed, and since the head unit I have is a DVD player as well, there is a wire that goes to the parking brake switch to tell the DVD player the car is not moving.....which I hooked up. I chose not to use the bypass they sell. I have NO idea why(nor do I give a shit anymore) but I'm guessing the parking brake connection did some wierd shit to the immobilizer or something...Needless to say I disconnected the damn camera and all wires associated with it and my Fit has been PERFECT. The system ROCKS, and my 51R has more than enough juice to keep things powered up. The car has mirrors that work quite well...don't need the damn camera!

 

Your car is upsidedown in a ditch somewhere, aint it?

Big congratulations, man.

 

My question is why would u need to install 2 amps? If the headunjt can properly power the 4 speakers all u need is an amp for the bass

 

Well....umm.....18 watts/channel vs. 100 watts/channel. Rather noticeable difference.