Lots of good info from others on this site. Mine is wordy, but these worked for me..I've owned my 90 Civic LX since new and I thought I would pass on three fixes..After talking to the local dealership, all of these are common problems to this vintage Civic and Accord..
My first problem (with not starting) was the ignition switch itself. I can't remember the symtoms (wouldn't crank??), but it was easy to identify because wiggling the key switch made it work. I ended up removing the switch and repairing it myself. I don't recommended this to everyone because 1) its hard to do and 2) it's easy to make it worse....The second time was the coil..She would crank, but not start...I unplugged one of the spark plug wires, put a phillips screwdriver in the wire and held it 1/2" away from ground, while some one else cranked her...No spark...The distributor cap looked worn but OK...I pulled the coil and there was an obvious burn mark inside the coil wire connector..I replaced the coil and all was fine FOR A WEEK...I screwed up here, because when I put the new coil in, I didn't have the conductor from the distributor cap plugged into the coil correctly (very easy to do on these). I had to replace the new coil AND the distributor cap this time...Burn marks again... My last problem acted like the second problem...Cranks, but won't start...This time, I had spark at the plug wire...Hmmm...no fuel???...I located the fuel pump (on top of the gas tank) under the rear seat (the seat is not fun to remove)..(It's in the trunk on the Accord)..I used one of those ice pick things with the light in the handle (and has a lead with an alligator clip)...There are more than 2 wires here because of the fuel gauge sending unit..You MUST have someone else cranking it while you are checking the light...one wire just barely lit the light...Hmmm..definetly not enough power for the fuel pump to work..As it turns out, there is a relay that applies power to the fuel pump when she is cranking and after she has started..Some people call this the fuel pump relay, or the roll over relay, or Honda calls it the MAIN relay...(BE CAREFUL with these checks, because there is a resistor in series with the pump and the voltage is not exactly 12 volts when working....more like 7 volts)..Rather than try to find this little devil, I went to the local Honda parts department and they were more than helpful...They knew exactly what I was talking about (Common problem for Civics and Accords)..and showed me the location in the drawings...Because there's a bunch of stuff in the same area, they pulled one off the shelf to show me what it looked like...under the dash, above the driver's left foot on the left fender wall and held by two # 10's...Anyway, other than CV joints, I've never had any other problems with this wonderful little car..Over 110K now..

One more bit of info...If you've decided the problem is the starter (or solenoid), after you have removed them, take out the 3 screws for the rear solenoid cover..there are some copper parts that are common failures for the solenoid..If you sweet talk a local starter rebuilder, he/she might sell you those parts...You will need a heavy duty soldering iron or gun..I understand that a new starter/solenoid costs about $1,000,000..(I don't know, I've never bought one).

 

cool, thanks for the info, i hope it helps people out.