2000 Honda Civc - Mystery Code Problem HELP!

Background info: I have a 2000 Honda Civic with 120,000 miles. The timing belt was changed about 10,000 miles ago, tune-up about 5K with cap, wires, plugs and rotor replaced.



I’ve been recently getting a check engine light. A diagnostic on the check engine light reveals TEN codes, all of them dealing with the miss-firing spark plugs, low compression, etc…



Compression is fine. Car runs great with no hesitation, no skipping. But the codes keep coming up after they’ve been cleared.



Any suggestions as to what might be the problem? FYI, this occurred BEFORE the tune-up so I know it can’t be anything to do with that.



Thanks in advance for your help.

One needs a scan tool which can read the FREEZE FRAMES and actuate the actuators. An online subscription to alldata.com (or, perhaps, your local public library) can provide the check lists procedures for diagnosing the DTCs (Diagnostic Trouble Codes). Or, you can pay a technician to do the trouble-shooting.

What the computer is telling you is that one or more of the cylinders is not contributing its share to the engine output. Since the compression has been cleared as a suspect, you have spark and mixture as the next candidates. So you may have a spark that is going to ground not at the spark gap at a certain engine speed or load. Also you may have a clogged injector that does not deliver the correct amount of fuel commanded by the computer and creats a mixture that is marginal for ignition. The miss need not be continous to set the codes and so may not be felt.

I know it’s tedious, but can you list all the codes that come up? It may help us make better guesses. If all cylinders seem to be misfiring, then I’m thinking either low fuel rail pressure or maybe a bad coil. Either of those could cause misfiring in all cylinders even after the plugs and wires were replaced.

thanks guys. I’ll get those codes to you by the end of the weekend.