Engine Saga Continues

I recently posted a problem about my Check Engine light flashing. They fixed it yesterday morning by replacing a wire/plug. They said a misfire had burned through the wire. The worksheet said nothing came up on the engine diagnostics, but they found a burned ignition wire. My original thread here: http://act…17942.page



After the fix, the car sounded better and ran smoother than it has in a while. This afternoon, I went on a long drive, covering both city streets and highway. Got off the highway, stopped in a store for 15 minutes (so it cooled a bit, but not totally), then started it up again. I smelled burning rubber briefly, then that stopped, but the engine has a “rough idle” again, and it feels jumpier again.



Any ideas? Could the same thing be misfiring again, and if so, what would that be? Could this be due to some underlying problem that isn’t showing on the engine diagnostics?



For the record, no alert/alarm lights came on. It took 20-30 minutes of driving (hit every red light) to get back. Do I dare drive it again?

It’s a 1999 Civic LX with 150,000 miles (50K on timing belt). It’s 10 years old, and will have failures. Can you open the hood and look at the stuff in the engine bay? You might find a clue. Otherwise, I don’t have a clue.

Considering you had a burned plug wire these guys should have considered a faulty spark plug as step one. Since the plug would be removed the compression should be tested to verify there is not a mechanical problem behind the plug misfire.

Think of the spark jumping the plug gap and the spark burning through the wire as a constant battle going on. The spark will always take the easiest path to ground. Eventually a plug that misfires bad enough will cause the spark to burn through the wire instead. Install a new wire and you’re back to the path of least resistance - forcing that spark to jump the plug gap.
At least temporarily until the new wire burns up.

If they did not replace the plugs and check the compression while the plug was out they did not perform the job as properly as they should have IMHO.
I have no idea why the CEL would not illuminate and no codes are present.