when doing a valve adjustment,does it involve the distributor at all?

 

No, I don't think so (see pictures for 96-00 Civics).

 

ok thanks. i just did a valve adjustment but it didnt solve my knocking noise.
The idle is fine and doest fluctuate, but the noise the engine is making comes and goes but it constantly taps.
It sounds like its coming from the bottom end.
any ideas?

 

Check that the sheet metal cover plate on the very bottom isn't hitting the flywheel, or maybe a bad motor mount.

If it really is inside the engine, low pitched knocking from the bottom of the engine is ominous, means the bearings are shot. Typically this results from running out of oil or never changing the oil and getting sludge buildup. You can try using heavier oil but likely you're going to need a new engine soon.

 

Engine Noise Diagnosis 101
http://remanufactured-engines.com/page4.htm

 

could it be piston slap?

 

thanks for the link.
ill see what i can do

after reading through the link, i think it could be piston slap now.
how can this be fixed, or is my motor just shot?

 

i have a low pitched knocking noise too. i don't think it's the same engine. i never really noticed it before i unsucsessfully tried to remove the crank bolt (lots of torque applied by holding the flywheel with a screw driver) i'm thinking i MAY have a cracked flex plate but not sure. took off the inspection plate and everything is fine from what i can see. took both bolts off the motor mount but the noise is still the same, even when jacking up the engine and putting tension on some of the other mounts. it doesn't sound like it's in the crankshaft though. it seems like the noise is on the top of the engine.

 

could be a worn camshaft. do these have hydraulic tappets/lifters/buckets or what ever you call them?

 

No they don't have hydraulic lifters, that's why you have to adjust the valve clearance manually once in a while to compensate for wear.