jamesd86

Hello all, just recently purchased a 97 Civic EX, 1.6 vtec, automatic transmission with almost 200k on it. No major problems at the moment except for a really rough idle, especially when the a/c is turned on. Well, really whenever there's a load put on it...like, touch the brakes, turn the lights on, turn the defrost on...anything besides just running at idle will knock the rpms down alot. Usually will go from 800(+-50) to bouncing and almost stalling. My thoughts are the alternator needs replaced, just wondering about a second opinion.


For the weird idle...When i'm in park or neutral and I tap the brakes, the idle will drop quickly..but if I pump the brakes a few times the idle will actually shoot up and hit around 1100 or so. Thoughts?


And last question(for now -.-; )...when i'm on the highway doing about 60 or so, should I be taching about 2500 rpm?? I'm used to my Blazer that would be about 1400 at that speed.

Thanks for any help.


EDIT: forgot to say this thing is like bone stock...aftermarket cd player and remote start. the rest is stock.

Former User

Pull out your handy-dandy multimeter and set it to measure DC voltage. Compare the voltage across the two battery posts with the engine idling under no load versus high load (with the high beams and rear window defogger on).

joeshmo

A good alt will usually put out more than 13 but less than 15v to the battery. Mine does 13.7 when the engine is running well.

jamesd86

So just hook up to the positive and negative and monitor the level as I put the engine under load?Have to pick up a multimeter(probably a good idea if I'm going to keep the civic as a lot of the trouble shooting calls for using one no?) in the morning. Will post result of test.

joeshmo

Yes, multimeters are great tools to have around. I have 4. Measure the voltage between the two terminals of the battery.

jamesd86

Well, alternator checks out good

I'm not sure what's causing it to bog down now

I can deal with just turning the a/c on/off at lights or when i get moving...my wife..not so much..in park the compressor kicks on and the engine gives one hell of a shake, maybe low or overfilled?(the guy i bought it off of said he had filled it beginning of summer maybe?)

battery w/o load 14.3
battery w/ load 14.0

i assume that's good.