I have a 93 civic with a h22 swap.
The air/fuel gauge tells me that the car is running lean and when I replaced the spark plugs, the plugs had red stuff on the spark plug tip and I also saw like red dust on cap and rotor. the car also hesitates when I'm drving.

 

did you paint the pistons

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jdm knight &raquo;</TD></TR><TR><TD CLASS="quote"> I have a 93 civic with a h22 swap.
The air/fuel gauge tells me that the car is running lean and when I replaced the spark plugs, the plugs had red stuff on the spark plug tip and I also saw like red dust on cap and rotor. the car also hesitates when I'm drving.</TD></TR></TABLE>
Did you change the cap/rotor as well? Is that "red stuff" rust by chance?

Also, if your using an Autometer or other narrow-band "AIR-FUEL" gauge, dont even bother believing what it says. It only reads like 14.0 to 15.0 anyways.

 

red dust in the cap should be no big deal. all mine have that. the red on the plugs would be from an octane booster, if you have used any. bad for plugs. a/f gauges are, pretty much, only useful for letting you know when your O2 sensor is bad. .. but when it DOES go bad, you usually get a very rich condition.
if your car is running very lean, the plugs will be pretty white from the high temps, not red.
i'd say you have a problem due to the swap. something is not right.
injectors?
fuel pump?
man. it could be ANYTHING.