I was driving home last night and my car started running very very rough all of the sudden. The CEL came on and it gave me codes 0300-0303 and 1399. It runs rough at idle and in all gears and if I give it a lot of throttle. However it runs fine at high rpms (4k and above) with low throttle. Fluid levels are good, spark plugs are ngk and have maybe 10k miles on them. Wires have maybe 40k miles.

Looking around it seems that others having this problem have needed to change the cap, plugs, and wires. I was wondering if those things being bad would cause it to start so all of the sudden. I had been driving fine for about fifteen minutes when it started. I was also wondering if it might be a bad ecu/maf/o2 sensor.

The car has 183k miles. Its a 1999 civic lx and its full stock.

 

also the rotor. also could be timing.

 

Yea I saw those as well. I was just wondering if it is more likely one thing or another before I replace sensors/plugs/everything else and spend more than i need too.

The timing belt was changed at 110k so its getting close to needing to be changed. I dont know if the timing is off but I havent had a problem in the 60k miles i have had the car til last night. I use injector clean every six months or so as well. I havent check compression/vacuum leaks/valve clearance as I am away at college and dont have tools with me but my parents live close enough to get to on weekends. Assuming the car runs well enough to get there.

 

I have the same car with just about the same amount miles give or take a few. Any way i had the same problem and i change every thing from spark plugs,wires,cap and rotor, and ignition coil and still did find the problem. Took it to my local junkyard and their mechanic was able to find the problem. My
4th cylinder fuel injection wasn't firing he did something with the wires and got it to work.
Maybe you have a bad fuel injection
The tool he used is called a EFI quick probe.

 

Just gotta start trying each thing. Visually inspect each thing. See if you're getting good spark. Look at your cap/rotor. Wouldn't hurt to do a compression test/leak-down test.

 

I also had the same issue with my GSR and I had done all the simple things as in Tune up replaced Fuel injectors and o2 sensors but still didnt get rid of that CEL Im guessing either my cat being bad(code p0420) was the problem or my Valves needed adjustment if I where u i would pull each plug out and look if one of them looks more burnt? or get a compression test and check valve adjustment

 

I have an 02 Civic with 105k and had the check engine light blink a couple times when I slowed down to a stop. It sputtered a little and then the light went out. About 10min later it came back on for good. It was running rough at slow speeds and better at higher speeds (freeway). I had a misfire cylinder 1 code (P0301) and a running rich code (didn't get the #). I figured the #1 plug went bad so I put in 4 new NGK's and it did the trick. Guess it just all depends...

 

Thanks for the suggestions guys. I finally got a chance to look at it. Had to wait til the weekend as a friend of mine with a decent amount of mechanical knowledge had tools and could help.

We checked the spark plugs. Three were perfect and one appeared to be slightly oil fouled, also the one that was oil fouled seemed to have some sort of small oil leak into that cylinder. The other three cylinders looked good. Checked to condition of the distributor and wires and they were all producing a good spark.

We also ran a compression test. The compression test was good. All cylinders were within about ten psi of each other.

I havent replaced anything yet and the condition has only worsened slightly but now the CEL flashes at me. I have stopped driving it expect for today when I drove the 15min to and from my friends place.

On the way home I noticed a slight amount of white smoke from the hood and tailpipe. It evaporates quickly and smells like exhaust or maybe slightly like burning rubber. The point the smoke was coming from under the hood appears to be from right under the lower part of the heat shield on the headers. The engine is not overheating and all fluids appear to be good. The antifreeze may be a little low in the reservoir but I don't think it is below the minimum.

Im not sure what the next step is. I think maybe the head gasket may be shot and needs to be replaced. I guess that would cause the fouling in the one cylinder but I dont know that it would cause the misfires on three cylinders. Any help would be great and ways of checking the things as well since my budget, as is all of ours, is limited.

Thanks guys

 

If it was a headgasket i'm pretty sure it'd show in the compression test. It's weird that your compression test showed up fine. Did you do a dry/wet compression test?

 

Im not sure what a wet/dry test is. I followed the write up from the link in the faq section. I didnt do a leak down test though. Something is definitely leaking into the engine from somewhere.

Thought I would post the numbers for people to look at. If I remember correctly it was 185 190 180 195.

 

Bump for some help. I havent been able to work on it because of school and work, but I would like to be able to try some stuff soon. Someone suggested I should check the timing and the fuel injectors. How do I go about checking the fuel injectors? Also if its the timing that is off then do I just need to reset the timing or is it time to replace the belt and stuff? I was going to replace the belt in the next 10k miles or so anyway but I'd rather not go through all that work if the belt is fine and I can just reset the timing.

Any help is appreciated

 

Can anyone help me with the names of reputable mechanics in the orlando area? I searched on here but everything I found was close to ten years old. A lot can change in that time. I havent lived here long and I have yet to need any car repairs until this.

 

Basically you do a compression test like normal, then add a little oil to the cyl to see if the compression goes up, to see if the pistons are bad.

If you have one plug that is oil covered it will cause it to run like you said, might be a sign of a bad valve seal, or piston (but the numbers are solid might be the valve seals)

As for the smoke, take off the heat shield and see if the exhaust mani is cracked, there is a possibility that will alter the way the car is running and say for instance the car is lean the computer will richen up the mix and maybe foul your plugs.

Side note: the black on the plugs could be carbon not oil.

 

White smoke out of the tailpipe is called steam. Steam is caused by water getting into the cylinder(s). Water gets into the cylinders because of a bad intake or head gasket. If you have a cracked exhaust manifold, it would account for the white smoke under the hood, just is coming out before it reaches the tailpipe.
Coolant level shouldn't change, it is a closed circuit and the coolant has no where to go. If it drops, there is a leak somewhere.

I think you may have just caught the head gasket as it is is starting to go/leak. If you continue to drive the car the smoke will get worse and it will run crappier.

Open your radiator cap and start the engine....are there bubbles? Does it blow the coolant out of the radiator? If so, you have a bad head gasket.

 

^^^ yes, but OP said the plug(s) were fouled. With a HG water leak the plug and cylinder/piston look brand new and shiny. OP what do the plugs look like and piston tops?

 

I had the same problem. And i couldn't figure out why it was throwing these random codes. So i picked up some wires and plugs from my local auto parts dealer. After i put them in i cleared the code and drove it a while. The light popped on and it was like that for a week or so. It was running a little rough and it just cleared itself. No more light or running rough. So you might have the same luck. Do the plug wires cap rotor and injector clean clear the code and drive about 50 miles or so. It might not pop back up.

 

White smoke can be steam and usually is because oil usually has a blueish tint to it. However steam doesnt smell like burning oil and I have a strong smell that is what me and like six other people I have had smell it think is burning oil. It smells very... burning rubber/plastic-y. I think I'm burning oil somewhere.

The one plug could be carbon fouled instead of oil fouled and that is a possibility. I hope it is just the head gasket though.

Well three of the plugs look pretty normal and three of the cylinders look nice and clean. One plug has oil/carbon on it and that cylinder has colors that look like oil are leaking in it. Not sure what the pistons look like as I didnt go that far into it. This is just from looking down into the spark plug area.

At this point I have dropped it off at manic mechanic over here in orlando and will get an estimate tomorrow and see what they say. I couldnt find if honda acura specialist was still around and was a bit time crunched. I will see what they tell me and go from there.

I didnt want to just replace some wires, wipe the code and wait for magic to happen. It already happened once with a rough idle problem I was having like two years ago and just stopped for no reason. It has always bothered me and I have been waiting for something bad to happen because of it.

 

Got my car back today. Apparently me and my friend who helped me(mostly my friend because he is supposed to know what he is doing) were wrong about the plugs and such. One of my wires was bad as well as the cap, rotor, distributor, and ignition coil were bad. It was all replaced and is now running fine.

Also I do have a crack in my exhaust manifold so I need to take care of that.

So i can either replace what I have now, which is like $300 just for the manifold and cat. Or I can replace it with a header and cat. Is that correct?

Is there a benefit to a aftermarket header and cat other than a almost insignificant boost in hp? Will it affect gas mileage/ be super loud? I dont have any other mods on my car and dont care for it to be super loud. I have noticed that some people doing this as the cost is similar.