Vehicle Jerk to Subwoofer Beat While Acceleratng

I have a 2011 Range Rover Supercharged (full size) and for like 5-6 years I didn't have any problems but now when I am accelerating, the vehicle slightly jerks when the subwoofer hits. If I am driving at a constant speed, you can feel the vehicle lose some power as if you let off the gas and on again very quick or quickly tapped the brake; you can also see the bump in the RPM on the gauge as well. When climbing a hill, it is very noticeable too. We first thought it was an old battery problem and replaced the battery; that didn't help. Next, we found out the alternator had issues and that was replaced with a new one; that didn't help with the jerking. I am about to purchase a new capacitor, likley a 3 farad and installing that to see if it gets better. Does anyone have any idea where the problem might be? The set up is as follows: 2 Alpine Type X suboofers 2 Alpine PDXM12 1200W amplifiers 1 Farad Pheonix Gold Capacitor Thank you.

The vehicle has keyless push start

If you're using a factory alternator (150A), you're trying to use more power than it can provide. I'm in no way affiliated with this vendor, but here are some available high output alternators: http://www.qualitypowerauto.com/item_379/Land-Rover-Range-Rover.htm (never tried them, just found them in a Google search)My ex once told me I have a perfect face for radio.

I have considered purchasing a high output alternator but it just doesn’t make sense since everything worked just fine before with the factory alternator and battery for several years..

You have 2 amplifiers that can pull 100 amps a piece, and your factory alternator is only rated at 150 amps. If you turn off the system and/or remove the main fuse under the hood, does the problem remain? How about at lower volume levels? My ex once told me I have a perfect face for radio.

With the sound system switched off or at low volume, it is fine and no jerking or anything

Well, there you go. Until you get a higher output alternator, keep it at lower volumes. You might even consider removing one of the two amps and wiring your two subs in series to alleviate your demand on the alternator.My ex once told me I have a perfect face for radio.

As I mentioned before though, I never had any problems with the factory alternator for several years.. I also replaced it with a new factory one recently..

jasdip wrote: As I mentioned before though, I never had any problems with the factory alternator for several years.. I also replaced it with a new factory one recently..

There's your problem. Make sure your belt tensioners are properly installed. Did you do it yourself or have it done? If you had it done, go back to the shop and talk to them.Support the12volt.com

Do we even know for sure it is electrical? It could be caused by the vibration of the subs. The only way I see to figure out which is to mount a charged battery and temporarily connect the amplifier power wire to the new battery. You will have to ground the new battery and the only connection to the positive terminal will be the amplifier power wire.