rpm's dropping with new system

Daher2323
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hey guys i put my system in my car (12" re audio sx, ed nine.1 amp) and when it is turned up my rpms will drop about 300 when the bass hits. any ideas for a fix for this without spending alot on new alternator/battery? I did the big 3 but that did not fix it //content.invisioncic.com/y282845/emoticons/eyebrow.gif.fe2c18d8720fe8c7eaed347b21ea05a5.gif

 
I say a Geo or Aveo. Otherwise, you should have your alternator checked, badly. If it drops 300 RPM per hit, your alternator is basically jamming up the cars performance by resisting the belt rotation in an effort to produce enough energy for your system. There could be other problems at root, but I would start with the alternator, and then battery.

 
What voltage and amp capacity is your alternator?

For example, mine is a 14 volt with 75 amps to play with, stock.

I cannot imagine yours being much smaller if at all, because Subaru's have small alternators.

 
the weird thing is...my lights dont dim and never have. the only thing ive noticed is the rpm's drop, which makes it very hard to drive because i have to compensate while shifting for that rpm drop. any suggestions?!?

 
Haha, that is just weird. Your accessories (lights) are supposed to dim before anything else is affected.

Something is wrong, either with the car or the install. Did you have any difficulties installing the system? Any blown fuses? or did this only happen after the install at a shop?

Need much more info regarding the entire setup, and ANY issues that came up.

 
zero issues occurred during my install. everything went extremely smoothly and fuses have never blown. I installed system, turned on car, havent touched it since. Any ideas?

 
have you thought of doing dual runs of wire for the big three, also are you sure all the conections on the big three is tight and secure. Make sure the connections are tight on the amps also.

What size wire did you run for the big three

 
What is bugging me is that you are saying that it bogs down when it hits. My only thought is that somehow you are drawing enough of a drop in voltage to start confusing your sensors, and therefore your sensors are adjusting AFR's and other various mixtures and timings to make up for a false reading. Usually sensors 'sense' the situations somewhere 100 times per second or more, depending on vehicle make, etc...

But, usually the computer will automatically tap into the existing Accessories in order to avoid these complications. Hence the reason why when your alternator dies and your battery slowly drains running all of the cars systems (while driving) your head unit will shut off, and all of your accessories, which will buy you a few more minutes. The computer is key in this situation.

I would REALLY go somewhere and have your alternator checked, and then if that clears, I would have your car hooked into a proffessional OBD-II reader (or whatever diagnostics are on your car. By the way, what CAR do you have?) and see if the car's ECU has been recording sensor malfunction, or low voltage warnings for key electrical components. When a sensor goes bad, these kind of 'freeze' frames are sometimes recorded, and the code will be ultimately recorded on the memory.

 
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Daher2323

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