Frustrating mystery problem with 2004 Honda Civic si Coupe

So I bought this car from a neighbor back in June. It drove fine for about 3 weeks, and then one day when I went to start the car, it acted like the battery was going bad. This didn’t make any sense to me, because the battery had just been replaced a few months before I bought it. It was a weekend, and the car seemed fine otherwise, so I figured I’d just take it to a mechanic on Monday.
The next day I drove it to the grocery store, and when I went to start it nothing happened. The electronics came on, but it wouldn’t start. No cranking, no clicking, nothing. I finally got it to start by pumping the gas while turning the key. However, even after I got it to start, everything electronic in the car would shut off and then come back on again randomly, and the car would try to stall out every time I came to a stop if the electricity happened to be off. After getting it home, I couldn’t get it to start again at all.
Thank God I didn’t sell my trusty old '97 Toyota Tercel. I have driven it across the country and back four times, it has 281,000 miles on it, and it has never given me any problems. That’s what I’ve been driving since all of this started. And I got the Civic to replace the Tercel. Now I’m thinking I might just get rid of the new car and keep the old one! Haha!
I couldn’t afford to have the Civic towed to a mechanic, so I had my mechanic friend come and look at it several weeks later. The first thing he thought it could be was the battery, so we went and had the battery tested. Sure enough, the battery was bad, so we took it to wal-mart (where the battery came from) and they replaced it with a new one.
Fast forward to three weeks later: all of a sudden I’m having the same problem I had before. Slow to start this morning, and then this afternoon I’m driving down the highway and BOOM everything electronic SHUTS OFF, all gauges drop down to zero, and I feel the car lose a little power. It still drove because it was running on the alternator, but the electronics kept shutting off and coming back on again. It got to a point where about every other second it would blink on and then off again. When I got the car home, I shut it off, switched cars and continued about my business (all of this happened while I was taking a car full of kids to their parents). When I went to start the Civic after getting home, all of the lights came on but the car would not start.
I don’t know what to do. I can’t afford to take it to a mechanic, so I’m kind of at my wit’s end at this point. Please help??? :frowning: Any information on what could possibly be wrong with it would be extremely helpful. Thank you in advance!

So when you tested the battery, did you/your friend test the alternator too? It might be simply a case of the battery not getting enough charge and eventually going dead. You have to test the voltage when the car is off (~12 volts) and then when it is running (should show ~14 volts) and see if the alternator is charging. Most car part stores will do this test for you with their gizmo free with the hope of selling you some parts.

I will also check all the connections, including the battery and also the ground/negative side to the body.

Have someone check the Electronic Load Detector in the charging system.

The ELD tells the computer the electrical requirements of the vehicle. The computer then adjusts the output from the alternator depending on the signal from the ELD. This saves fuel.

If the ELD has failed where it’s telling the computer that electrical requirements are low when they’re not, the computer will reduce the output from the alternator without turning on the charging/battery warning light. And this will result in a low/discharged battery.


Good posts above. The original battery might have still been good btw. The proper way to test a battery is to charge it fully first, with a bench charger. That takes some time to do – can take up to 24 hours – and so is often skipped. But it is the best way to check a battery condition. Do you know a full charging was done first? If not and you still have that original battery, suggest to do that.

Other things that could cause this symptom

  • Faulty alternator or alternator drive belt
  • Battery connections corroded
  • Faulty ignition switch
  • Faulty starter motor (wouldn’t explain all the symptoms, but could be a part of the problem.)
  • Faulty wires or grounds.

You might need to take this to an auto-electric specialist. Especially if the problem is the last one on the list. One time I had a wire splice inside a main cable bundle eaten away by some battery acid, and it took a lot of detective work to figure that one out.

Inspect the battery cables and ground connections. The most likely cause.

Any add-on, non-factory electrical devices (alarm, lights, audio, etc.) would be high on the list of suspects.

Is the hood or something else shorting out the battery?

Can the neighbor who sold you the car give helpful information?

I’m wondering if the neighbor sold the car BECAUSE of the problems

Naturally, he probably wouldn’t admit to this, even if it were the case

It wouldn’t be the first time such a thing happened


I might throw out the possibility of a failing ignition switch. Some slightly earlier models were under a Recall for failed switches but I do not believe the 2004 is.
However, many cars not covered under a Recall suffer the same problems as the ones that are. Back room politics limits the number covered.

That could be easily checked with the car inoperative and someone with a working knowledge of electrics.

Switches have been a sore spot for many years with Hondas. Plastic switches and high current which includes the fuel pump load is what causes them to fail.

I also suspect the car has done this before and the neighbor if questioned would claim that it never did that with them.

I like the idea of the ignition switch

Lesson for any casual readers: Never buy an 11 year old car without $1,000 in the bank to fix the reason the previous owner dumped it.

Absolutely agree with insightful. You’ve got to put extra money aside to bring any car up to standards again. Even with a new car you need extra money for new supplies, repair manual, etc.