Hi;

I have a 98 Civic sedan with a 1.6 engine. The Check Engine Light is on, but there are no codes stored. I am using a high dollar scanner...Snap On Verus. I can communicate with the PCM and run tests. I can even clear the codes and the CEL will remain off for about 5 seconds, then pop right back on. When I check for codes, all I receive is "No Codes Present" I checked the permanent and temporary, and I checked for Engine, Trans, Anti-lock brakes, and Air-bag. I also disconnected the battery terminals and touched them together to discharge the capacitors in the pcm. CEL goes off, but illuminates with in 20 seconds.

Any idea what is going on?

 

ECU is known to be good? That's all I can think of