Rep Power: 0

Hello, I have a 2002 Honda Civic EX 5 speed. I have been having an issue where my check engine light repeatedly comes on every 5-10 days. It will stay on for a couple days and then turn off and then 5-10 days later it comes back on. The codes are always cylinder misfire codes, sometimes a random misfire, sometimes a misfire in one cylinder or sometimes in all 4

I have taken it to a Honda dealer and a mechanic who is a friend of mine, and neither can find a issue. The car rides normal, if it wasn't for the light I would not even suspect an issue, gas mileage is normal everything seems fine, except for the light. I also had the spark plugs changed and used a can of fuel injector cleaner, came back on.

My mechanic friend said he thinks it is a computer that needs reprogrammed, and I was wondering if anyone had heard of this happening. The honda dealer said they thought it was a bad coil pack so they changed one for me and reset the code, and then 9 days later the light came back on. Any idea's on what it could be, does the computer issue sound like a possibility? Any help would be great, I have an after market warranty that is going to expire in the next couple months and I really need this resolved before it expires! Thanks for any help!

 
Rep Power: 200

Are they looking at it with the light off? You need to get it checked out with the light on. That way we can decide if the computer is legitimately turning it on due to a short or the cluster or something....

 
Rep Power: 0

No the last time I brought it into the dealer the light was still on. They reset it, but like I said 9 days later it came right back on and has now been on for almost three days now. It still drives perfectly normally, great mpg, starts right up, idles very smooth. The only symptom is the CEL.

 
Rep Power: 0

I wouldn't condemn the computer at all... Bring it back to the dealer since they didn't fix your problem and ask them to check the valve clearance...

 
Rep Power: 186

Your EGR passages might be clogged on your intake manifold.

 
Rep Power: 0

I had random misfire codes, sometimes all 4 when my headgasket was bad. Just a thought.

 
Rep Power: 0

Just an update on this in case anyone else experiences similar issues. I took it back to the dealer to look at, and they don't know what it is, gave me some crap about it being spark plugs. They did realize that when this first started happening, the first thing I did was change the spark plugs and it came back, so it is unlikely it is them.

I told them to look at the valve clearance and adjust, and they did this for about $100. I should have it back this afternoon assuming all goes well. If the light comes back on I will update this post again.

Thanks for all the suggestions to everyone! Also for people experiencing this issue I did find this good article which may or may not help you:

http://www.import-car.com/issue/article.aspx?contentid=85145

 
Rep Power: 0

My suggestion is reset the computer. Under the hood fuse box should do it.
~remove fuse box cover
~locate fuse 19 (80A fuse)
~remove it & leave it out for 10-15mins
~then put it back
~start car and let idle for 10mins.
~ gone for a long time!
Hope this helps.
Keep updated if it happens again

 
Rep Power: 0

what is a valve clearance and adjust? how does it happen? what r some symptoms? What does the dealer do with those symptoms? to the OP for paying $100 what did they look at?
It seems i have a similar problem with my 03 civic.

 
Rep Power: 0

I have a 2002 Civic 5-speed. I have the same problem and haven't been able to figure out the problem. My Engine Check Light will come on about every 200-500 miles - with usually P0301, P0302 and P0300 (misfire in cylinder 1, 2 and random) (I usually get these P0301 code). Every so often the car will idle a little rough and the code will come on soon thereafter.

I had another shop look at it and over a period of 4 or 5 visits they ended changing plugs, valve adjustments 3 different times (each time I brought the car back they said the valves need to be adjusted), changed all 4 coil packs. They said the only other thing to try will be replace fuel injectors but it will cost about $600. I told them I will wait.

I was so frustrated with bringing the car back, I decided to buy a code reader to see if I can figure out the problem as well as reset the CEL myself. I have tried several things over the last 18 months but I still haven't figured it out.

Anyway, to recap with I did, I tried fuel injector cleaners (different brands like Chevron and Sea Foam, ...) but the light keeps coming on.
Since it is usually cylinder 1 and 2, I switched the plugs and coil pack from cylinder 1 and 2 to cylinder 4 and 3 respectively to see if the error codes will change and needless to say, the error codes kept coming up P0301, P0302 and P0300 so I am pretty sure it isn't the plugs or coil packs.

I don't know if I need to replace the fuel injectors and/or do another valve adjustment. I just don't want to put more good money chasing a problem I haven't identified - if someone has any suggestions, I will also like to know what to do (I don't want to keep spending good money chasing this elusive problem).

 
Rep Power: 186

It's either your head gasket leaking fluid in to the cylinders and it's causing misfires or your EGR passages on your intake are clogged. These are the passages below from my intake when I replaced my head gasket. This was before I cleaned them. I have a 2002 EX auto.

HTH

 
Rep Power: 0

Had similar issue with my 2005 EX sedan. Changed plugs, coil packs, fuel ejectors and adjusted valves. Problem was an intermittent failing fuel pump. Unusual for a Civic but does happen.