Rep Power: 0

I drive a 2002 Civic with about 155,000 miles on it (no, I don't drive that much .... I bought it used in 2007 with 139,000 already logged).

About a month ago, the check engine light popped on while I was driving home from work (a sedate 4-mile drive along a standard city street). I took it to the mechanic. It threw codes for random cylinder misfires, as well as specifically cylinders 1 and 3. He recommended a general tune-up and cleaned the fuel injection system. He also replaced the spark plugs. All seemed well.

A few days later (after about 30 miles of driving or so), the light popped on again as I exited from the freeway. I brought it back to the mechanic. It threw misfire codes for cylinders 1 and 2. We reset the computer to see what would happen. A few days later, the light was back. Codes were for cylinders 1 and 2 again. The mechanic suspected the ignition coils, so we swapped 1 and 2 with 3 and 4 on the logic that if this was the culprit, the next codes should be for 3 and 4.

Eventually, the light was back on (this time it came on while parallel parking, after about 60 miles of total driving). Codes? Cylinders 1 and 2. One more re-set, plus replacement spark plugs just to be sure ... one more light on (this time while driving about 40 mph, after driving only about 10 miles). Codes for 1, 2, and 3 this time.

My mechanic is stumped. He suspected the fuel injectors, but now says he doesn't think that's it. The mechanic also floated the idea that it might be something loose in the wiring harness triggering the CE light, but I think that was based on my report that the light had once popped on while I was parking and moving the wheel back and forth (but that hasn't been true regularly). I'm not too mechanically savvy myself but am trying to help reason it out.

The car doesn't seem to be exhibiting any symptoms. Every so often, I'll get a shudder when I press the pedal down (like something in the engine has gone a bit out of whack), but it corrects itself if I ease off and try again.

Has anyone had an experience like this? Any thoughts on what the culprit might be?

And what would you do if this was your car? Would you just drive it and see what happens? Have the mechanic start trying things at random? (So far I've only paid for the original engine tune-up, and I'm on a tight budget for this kind of stuff.) Any thoughts would be appreciated!

 
Rep Power: 811

are you loosing coolant? could be a small headgasket leak. or clogged fuel injectors that are unable to vaporize the fuel. the car would still run okay, but not as well as it should. make sure you are using ngk or denso spark plugs only.

 
Rep Power: 0

Thanks for the advice ... I don't think I'm losing coolant (if so, not enough that anything has dried out or overheated yet), but will check. I'll also check the spark plugs in there. My guess is that the fuel injectors aren't clogged, as cleaning them was the first thing my mechanic did in response to the problem (not that they couldn't somehow otherwise be the culprit, but ... )

 
Rep Power: 0

Chicago Driver, I have an 01 hx civic and seem to have the same problem which started about a month ago. I have 215K miles and have had no problems with this vehicle, which is why I couldn't believe the check eng light came on right after the car passed the smog check, I mean within minutes and a few miles after the smog check! I am doing some troubleshooting with the service manual and will let you know what I find. So far the fuel pressure is OK as well as the valves, injectors, coils, and plugs. Next is wiring and the computer.

 
Rep Power: 0

My 2011 civic threw a misfire cel. Shut car off restarted 5 minutes later. Cel off. Been fine since. No codes either. Which is weird.

I may replace coils o. Principle of 208000 miles on original ones

 
Rep Power: 366

2011 have a very different engine compared to the 7th gen cars, post on correct section

Edit:
You actually have a thread going on.
Keep to it, spreading to others will not help you.

https://www.civicforums.com/forums/3...ine-light.html