HHHmm at the tender age of 47 I have a 4K amp in the jetta. Huh? did you say something? ;-) You have to ride in a car to appreciate the bass boost. from the outside it just sounds like noise.. but I likes it..
The addition of a Cap to your system will help out the peak draw moments but
the overall draw should be the same. The cap just buffers the peaks.
If you dont have a Volt/ohm meter then I would disconnect the amp and see if the problem is still there. If so then it isnt the amp draw.
Sounds more like an intermittent grounding problem? When the car accelerates or
as you come to a stop the engine will move around and if you have a wire that is
flaky..on the edge so to speak this movement may be all that it needs to ground out.
If taking the amp out of the picture doesnt solve the problem I would hunt for
either a bad ground or a wire grounding out?
See you at the next stop light! ;-)

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