This might be a little long, but please bear with me, I'd really appreciate some help on this one.

I have a 2000 Honda Civic CX (dealer offered to take the trade for $1k ... I was like "you crazy, jesus, you crazy!") and it's having some "fun" issues, which may or may not be related.

1) The electrical system seems all sorts of messed up - with the engine running, all the lights in the car (including headlights, and all the lights on the dash), will "pulsate" in sync (as in, bright - dim - bright - dim), about 10-20 times per second. Now here are the fun parts:

1a) The lights will also dim in tune with my music (ok, no mystery, really, loud thump of base = more current draw = voltage dip)

1b) The FREQUENCY of the pulses does not change with engine RPM, but the AMPLITUDE does. The "top end" seems to get brighter with higher revs. Actually, when this problem just started, it would only manifest itself at higher RPMs, and would also gradually fade away after the engine had been running for a couple minutes.

1c) When I hold down the brakes (and the stereo is not playing), the lights stop their little disco thing, and behave quite normally. My impression is that the "bright" pulses disappear, and the lights stabilize at the "dim" level.

 

2) In 2nd and 3rd gears (maybe also 4th and 5th but barely noticeable), the car will "buck" a little bit when accelerating in the lower RPMs (once you hit higher RPMs, it becomes less noticeable). Could this be related to the electrical issues mentioned above?


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So yeah, I would appreciate any help. If not specific advice for this problem, maybe some general first things to check for electrical issues (yes I'm a n00b). Thanks in advance!

-D

 

mmm... lay off the acid & the weed a bit?

 

Either that, or give some to the person I want to sell the car to?

How about something contructive, eh?

 

your alternator is dying. it will probably go any day now. exact same thing happened to my 2000 mustang.

 

ok, seriously tho- i owned a 1999 civic lx once upon a time, and i never had any electrical problems except routine maintenance- ie changing the battery, changing light bulbs, and changing fuses.

that said, based on the symptoms u described, it sounds like someone has done a poor job wiring an aftermarket stereo system in that car. or, it may have been in an accident and put together improperly afterwards. i'm no expert, but i think u start with the basics- ie check all the fuses, get a wiring schematic of the car, and then start troubleshooting section by section. or, might be easier to just take it somewhere and have them check it for u...

 

Get your alternator done. My old 97 ex was the same way. I put a system in it and i had all kinds of electrical hell. got the alternator replaced and never any problems since!

 

That's what I was thinking too... weak alternator, and slowly killing the battery?

Off the top of your head, how hard is it to swap out the alternator? Hopefully it's something I can do by myself. I will have to dig up my pdfs of the FSM.

Any other ideas appreciated

 

Alternator. Swapping it? Dunno... never done it on a transverse mount engine... so I can't say. But I don't think labor for this kind of thing should be too bad if you have a shop do it.

 

^^ yep, Your alternator is Dying and it is killing your battery with it.

replacing the Alternator on a Honda is very easy. Just make sure you tension the belt properly after replacing it

PS Higher RPMs tend to kill Honda alternators in older cars with aftermarket stereos. I had to replace mine 3 times in 4 years on my old CRX. and always after I took the revs up to the limiter (I should have invested in some underdrive pulleys maybe?)

 

I may try to do the swap myself (for a car that I want to sell, cost of alternator and maybe new battery is big enough, don't want to pay labor too :-D )... Plus it's good practice anyway.

Anyone have a copy of the FSM? I seem to have "misplaced" mine (even a terabyte of storage won't save you if you don't have the discipline to keep your stuff organized )

 

FSM???

All I have from my old '88 CRX is the Chiltron's repair manual.
Anyways, all you have to do is

0. disconnect the battery
1. loosen the idler pulley (to remove tension from the accesory belt)
2. remove the electrical conections from the alternator
3. loosen the bolts that holds it to the engine block
4. replace with the new one and tighten evrything back up

EDIT: Take it to autozone/advanced auto parts first. they can dignose your alternator/battery/starter and it is usually free.

 

swapping is easy, plus pepboys has them mostly in stock for about 130 bucks