Rep Power: 0

Hey guys,

Luckily this hasn't been a consistent problem, but at least once every week, when I start-up my 02 Civic Ex there is a misfire. The car won't start, but if I crank it the second time then the car will start up with no problems.

I've already upgraded the spark plugs a year ago. I have two 10w7 JL Audio subs, two amps, components, and a cap with a yellow top Optima battery to support the system. Whenever I turn the headlights on or the system........I encounter no problems, no dimming. The car runs great.

But its that once a week misfire. I took my Civic up to Auto Zone, and the alternator amps are a little short. The maximum amps on our Civics is 70 amps, but we average about 52 amps. My Civic was monitored at 31.5 amps so I'm thinking maybe the alternator needs to be changed out?

What is your take on this? Should the alternator be changed out, and if so then what aftermarket alternaor would be appropriate for my Civic? I would like to add that the battery is not the problem as the tester showed good results.

 
Rep Power: 336

fouled plug
bad ignition pack
messed up wires
alternator would not cause a misfire. it would cause the battery to not be charged enough to even start the car.
when it misfires is the motor hot or cold? whats the temp like outside? intake? check the filter? good luck

 
Rep Power: 0

Hi I forgot to add this misfire occurs when the engine is cold or hot. On startup in the morning it might occur, or later on during the day it might occur. I'm hoping its not a plug as it is hassle to change out plugs.

 
Rep Power: 453

well what you described doesnt sound like a misfire. If you had a misfire, you car will still start, but run rough. And if you were missing, your PCM will reconize it and throw a code. A misfire is usually when one cylinder is not igniting the air/fuel mixture, usually caused by a cylinder not igniting the mixture caused by a faulty ignition coil or bad PCM, a faulty or severly clogged injector or a possibly dead cylinder caused by a mechanical engine fault. Sounds like you may have a loose connection or something. When you tried to start it, did it just crank and not start. then after a second time start?

 
Rep Power: 0

Hi, yes when I tried to start it would crank but die real quick, but then I would crank again the second time and the car would start perfectly.

 
Rep Power: 453

yea thats not a misfire. Now, did it start up and die or just crank and stop? Just trying to get in depth detail.

If it just cranked and stoped, its a possibility you may have not turned the key long enough to let it start. I have always done that. You could have a possibly bad fuel pump or one starting to fail. Possibly failing crank position sensor. I used to see that alot on mercedes when I worked there. Sometimes they would crank and crank and not start, then other times they would start right up. I dont think the problem has anything to do with your alternator. Have you noticed any charging problems? The only thing I can think of to why it said it was only putting out 31 amps was because the person doing the test with the VAT didnt have the AMP probe in the correct direction. I remember getting false readings in school when we did alternator tests from having it on backwards if I remember correct.