I have a 03 Honda Civic EX with about 75K on it. Runs well and gets a solid 38 -39 mpg.

For about a 20-30 second period of time (usually a minute or two after it is started cold) it completely loses power. It will not rev up even if I disengage the clutch and may stall. So once that happens, I just need to wait for the 20-30 seconds and all is well again.

My thinking was ignition, so I started with the obvious and changed the plugs. At that time I noticed that one of the coils had a crack and had been sparking against the valve cover in addition to the plug. Last night I put a new coil and another new plug in that cyl and it ran great this morning. When I just left work it did it again.

What could cause this? I'm going to see if there are any codes stored on it later tonight. The yellow engine "emissions" light was on twice a couple weeks ago but shut itself off. This has been going on longer than that, though.

 

Two things:

First, sounds like you might check your Alternator... mine went out about 80K and did nearly the exact same thing you are describing (with the exception of the Emissions light).

Second, you may have Exhaust finding its way back in your air/fuel mixture... (clogged exhaust)... could be due to a bad timing belt or perhaps a malfuctioning valve on a single cylinder.

Both could cause the power loss you're experiencing.

 

Well, it looks like the #1 oxygen sensor is bad. I'll be thrilled if it is really that easy of a fix!

 

^^i strongly agree!! ive seen a bunch of these civic do this repalce it with an oem honda. that should def take care of it. as for the timing belt if it was off by one tooth car would not run at all

 

On the advice of the parts guy, I ran some Techron fuel system cleaner through it with 1/4 tank and ran it down the highway.

It seems to be running much better. Thinking it might be ok and hopefully do not need to replace the sensor yet.

Are the factory sensors worth the extra money as compared to the parts store version?

Anyone know how to reset the emissions computer without disconnecting the battery? I bought the car used and do not have the codes for the radio.

Thanks for the replies!

 

pay the extra money and get the oem sensor.if you pm me ill tell you how get the radio code

 

psst! .. ..

Radio Code Link from The FAQ's

 

Thanks again for the replies! I had found the sticker, or what was left of it. It was unreadable. That online link worked and I got the code. Not sure anyone would want to steal the factory sound system anyway.

I suppose I'll drive it and see if the light comes back on now. Who makes the oem sensor, Denso?

I did an online search for the Honda part # 36531plra01 which the dealer gave me and didn't find much. It is out of stock at my dealer.

On an unrelated note, my #2 trip meter only seems to make it to about 800 miles and then re-zeros itself. Is that normal? In my truck I use trip #1 for gas and trip #2 for oil changes and would like to do the same for the Civic. I didn't see anything in the manual about it.

Edit: Did some searching for 36531-plr-a01 online and most places refer to it as "downstream oxygen sensor". My code came up as "bank one, sensor 1" which they said was upstream, or the one in the exhaust manifold that you can see when you open the hood.

Edit 2: Glad it wasn't in stock! This thread indicates that it is a bad part #.


Honda Parts Online doesn't seem to give the part number.

Does anyone know what I'm looking for? 2003 2dr EX 5spd VIN# 1HGEM219XXXXXXXXX

 

the part# you should need is 36531-PLR-A01 go on bkhondaparts.com its a honda dealer selling parts online. you can look up your owm part.

 

Well, it took over a week to get the (factory) part and it is in now. The car runs great! A noticeable difference.

But, now the engine light is coming on and I'm getting a P0420 code. I reset it and it came back.

The cat better be good. It is less than a year old and is a factory part. And the gas cap is not loose.

I double checked that the new sensor is torqued down. Any ideas?

Is there a way to test the downstream sensor?

 

Eric any updates on what happened with your car? i am having similar problems. the car will start and run fine for half a minute, then it bogs out (seems like no ignition but i could be wrong) for like 20 seconds, then comes back to normal idle, runs for a minute, then bogs out again and is barely idling. this cycle repeats until the engine gets a little bit under normal operating temp; and then everything is completely fine. I'm throwing a ELD (electronic load detector), some lean A/F o2 sensor code, and gas cap code but im guessing none of these were accurate.

Any who just wanted to know if you fixed your problem, and if the light is still on because you might have a different year o2 sensor like in the other o2 post.

Also i am trying to figure out what is causing this idle problem. The heater in the o2 could be bad causing it to provide a false reading to the computer which might make it idle bad (and only work when hot), but i dont understand why the problem is so intermittent. It's almost as if the computer is only sampling that o2 sensor every other minute. I don't understand whats going through its "mind". Either way it's very annoying because its not exactly broke so i'm too lazy to really look into fixing it.

thanks.

 

Update:

The car has been running excellent since replacing the upstream oxygen sensor. No more hesitation when cold.

It took a long time for the computer to catch it and give the code. So if you're going through the same thing, then you may want to try an upstream sensor. I went with a factory part.

As for the P0420 code, Honda replaced my cat again. The car only has 75K, so the cat is still under warranty. They also replaced the downstream sensor and the ground strap to the engine.

It wasn't until after I replaced the sensor and the car was running well that the bad cat code came up.