Passing the California smog test if you have a ZC motor
By Ted Gutierrez
Livermore, CA

This is a collection of tips we recommend if you need to pass smog and you have a ZC motor in your Honda. Most of this is based upon personal experience trying to pass my 90 CRX Si w/ ZC motor in 1999 and 2001.
Special thanks go to Lee Lim (aka Outsane) of San Diego, M. Collins (aka Mykel), and Rodger Boles for their input for this article.
 
  Ok, The easy stuff first:

• Change your oil and filter
• Clean your air filter, especially if you have a K&N or other aftermarket intake filter.
• Clean & inspect your spark plug wires
• Replace your spark plugs with new NGK Copper plugs
• Set your timing back to stock (18 degrees BTDC)
• Run a lower octane fuel
• Be sure to drive your car on the freeway for at least 20 minutes to properly warm up the catalytic converter. Also, try to keep your engine running to the very last minute before having them perform the tailpipe emissions test
• Psychology is a powerful thing. Dress nicely and it helps if your car looks fairly mild. A "fast and the Furious" look-alike will not bring favorable results. DO NOT TALK ABOUT YOUR MODS! Sound obvious but sometimes we can't help ourselves. Just say to yourself, I'm a yuppie taking my wife's Honda in for routine smog. I know nothing about what is under the hood.
• Techs sometimes seem to ask probing questions, I believe the correct answer is "It was like that when I got it from the dealer. They had to smog it before I bought it right?" Followed by a straight face if you can manage it.
• From my experience of passing smog twice in the past 4 years (ZC), the techs in Northern California don't really look at the motor much. As long as it's a stock-looking Honda block and passes tailpipe, visual is usually guaranteed. If you have a VTEC motor, I suggest keeping your stock looking valve cover on, not one of the JDM red ones.

The more difficult stuff:

• Replace your catalytic converter if it is the original one. This made a HUGE difference on my ZC smog test and countless other buddies who passed smog w/ their ZCs. 
• Adjust your valves to factory timing specifications. If you're running aftermarket cams, swap your stockers back in.
• If the hood smog-sticker diagram is gone, the techs tend not to look up the specs on the engine. People often have to replace their hoods because of front-end damage and thus don't have the stickers. The tech tends to look and make sure all of the lines are connected and that the valve cover say Honda.
• Running some of that "Pass Guaranteed" stuff through the gas tank really does help. Make sure to follow the instructions. Some guys fill the tank with this stuff and then smog it while the detergent is still in the tank. Run it through and then fill it up with a fresh tank of gas.
• If you have a non-stock ECU (ie ZC, Integra, ZDyne, etc.) and your HC count is too high, but your CO is normal, swap your Si ECU back in. If your HCs are in spec but your CO is too high, switching to an Si ECU for leaner idle and 2500 RPM readings will worsen the problem.
• Replace your O2 sensor, especially if you have headers.

 

 

 

 

 

 

Honda CRX/Civic ignition Basics
By Dave Darling
Mountain View, CA

The ignition timing is a fairly important thing for any car. If your timing is too far advanced, you can get "pinging", which is a sign of detonation--and detonation is something you don't want in your engine. Set it too retarded, and you will lose power, and you can cause the engine to run hotter. There is a middle ground which Honda has found for us.

In this How-To I will describe how setting the timing is done on my 1990 CRX Si; other years and models will be different in detail but should be pretty similar overall. When in doubt, find yourself a Helm's manual to see how Honda thinks you should do this.

You will need a few tools for this job.
First and foremost, you will need a timing light. Mine is a Craftsman from Sears, but any decent-quality one will do. You will also need a 12mm open-end wrench, and I've found that having a 12mm socket, a ratchet handle, and a 3" extension to make the job easier.

The first thing you do is let the engine run until it is nice and warm. Honda recommends you wait until the cooling fan comes on at least once. I figure about 5 minutes of idling is fine unless the weather is *really* cold... There is a connector that you have to use when you set the timing. On my 90 Si, it is in the passenger footwell on the side wall just in front of the door (Fig. 1). It should have a yellow cap on it, but mine didn't. The connector should have a brown wire and a green wire going into the back.  On 88-89 models the connector is under the hood, on the driver's side of the engine compartment. It's located just above the window washer fill bottle (fig.1-2) You want to short those two together to tell the car's computer not to monkey with the timing because you are trying to set it. The easiest way I found was to take a piece of wire, strip the ends, and shove them into the connector (Fig. 2). The length doesn't matter--I used a long wire because I had it on hand.

Open up the hood so you can get to the top of the engine. Next you need to hook up the timing light. There are usually three leads on the light, a black one and a red one close together, and a separate clip-on lead. You hook up the black lead to the battery ground post, and the red one to the battery "hot" post. (See Fig. 3)

Then you hook the clip-on lead to the #1 spark plug wire (Fig. 4). Some timing lights have a knob on the back that changes when the light goes off--if yours does, set it to zero.

In Fig. 5, the timing light is all plugged in and sitting on the intake manifold. If you turned the engine off to hook up the above stuff, start it again. The engine must be running to check the timing. Take your timing light, and aim it down at the crank pulley. On the timing belt cover, you should see a Vee notch and a pointer. Look so that the two are lined up, and then look at the area of the pulley that is in line with both of them. Point the timing light at that area, and pull the trigger to make it flash. You should see some notches on the pulley. Fig. 6 shows--if you look carefully--how they should line up for an Si. There are three notches very close to one another; the center one is painted red. The pointer and Vee should line up with the center notch when the timing is correct for an Si or DX. An HF uses a separate notch that is over to the right a little bit (see Fig. 7) and is painted white. This notch is a lot harder to see than the others. If the correct notch shows in the light, you're done! If you cannot find any notches at all, keep looking. Make sure that the knob on the back of the timing light (if any) is set to 0, and make sure that the timing light's clip-on lead is connected to the #1 spark plug wire--the far-right one.

What if it's a little bit off? Then you need to adjust the timing. That's where the wrench, socket, ratchet, and extension come in. There are three bolts on the distributor that you have to loosen. The top one (Fig. 8) is best done with the open-end wrench; a socket doesn't really fit on it very well. This bolt head had most of a plastic cover on it, which crumbled when I tried to remove it. The two lower bolts are tough to get a wrench on, but the socket on a 3" extension seemed to work well for me (Fig. 9, Fig. 10). Loosen these three bolts but do not remove them. Now go back to your timing light. Take a look at the notches. Then twist the distributor body one way or the other, and see how the notches move. You'll have to go through the "twist a bit, look" cycle a few times before everything lines up. Once it does, then tighten the bolts on the distributor. Check the notches one more time just to make sure nothing moved while you were tightening the bolts.

You're done. Unclip the timing light, unplug your jumper wire, turn off the motor, and close the hood. (Make sure that you get all the tools out of the engine bay first, or you may need my next "How-To" article, "How to Remove Your Front Bumper".)

 
 

How to Remove Your Front Bumper
By Dave Darling
Mountain View, CA

Sometimes you just have to remove your front bumper. If the headlight lens on your 2nd-gen CRX, for instance, breaks--removing the bumper is the first step to replacing it. Or, for instance, if you are dumb enough to close the hood on some tools and it wedges the hood shut. (See the "setting your timing" article...)

This article describes how to remove the front bumper of a 1990 CRX Si. I'm sure that most or all 2nd-gen CRXes are the same, and the 1st-gens might even be similar. The general procedure is to remove all the bolts and screws, and then pull the bumper off. The main part of the article will then be the pictures showing you where those bolts and screws are.

First there are two bolts under the bottom of the bumper (Fig. 1). Notice that I have hit a few bumps with the metal overriders on the underside of the bumper; they are pretty well scraped up...

Next are the screws at the front edge of the front fenders. There are two screws in each; one in the black trim strip (Fig. 2), and one a couple of inches below (Fig. 3). Note the screws are already removed in the pictures.

Finally, there are two bolts behind each of the turn signals. To access those, you have to remove the turn signals. Loosen the outer screw (only) in the turn signal lens (Fig. 4). This will allow you to swing the outer end of the light forward (Fig. 5), so that the light can be slid outward a little and then pulled out. That will show you the two mounting bolts behind the light (Fig. 6). Remove those. In the picture, the lower bolt has already been removed. My bumper stayed in place until all four bolts were removed; yours might or might not, so be prepared for it to try to fall onto the ground when you remove that last bolt. You may also need to wiggle the bumper a bit, or pull the ends (where the screws were) outward a little to get the bumper to move. Fig. 7 shows the car with the bumper sitting in front of it. The wires going to the turn signals are just long enough to let the bumper sit on the ground--if you want to actually remove the bumper completely, you should unplug the lights to allow you to move the bumper out of the way. Make sure to mark the electrical connections so you can plug them back in again later!! Note that you can see the windshield washer bottle below the left headlight, and the intake resonator would be visible beneath the righht headlight if the photo were taken from over by the right side of the car.

To put the bumper back on, you pretty much reverse these steps. I found that the bumper would stay put in more or less the right place if I hooked the ends around the brackets that the four screws went into. This made it a lot easier to get the various bolts started. I recommend starting all six of the bolts and getting them only finger-tight. This will allow you to fiddle with the position of the bumper before you cinch them down tightly. I also got the four screws at the ends of the bumpers started before I got any of the bolts tight--I did not want to have to loosen everything up so that I could get the screws started. It didn't seem to be much of an issue, but... The turn signals deserve a little more attention--you should either make sure that they are plugged into the wiring before you put the bumper back on, or make sure that you can fish the wiring through the holes after you put the bumper on. When you re-install them, you need to make sure that the mounting tab (Fig. 8) is hooked on the edge of the hole in the bumper. Then you can swing the outer end of the light in and start the mounting screw.

And that's really all there is to it. Six bolts and four screws (plus the turn signals) are all you have to pull to remove the bumper. It wasn't nearly as complicated as I had feared--I simply followed the diagrams in the Helm's manual and it came right off. BTW, I was able to un-stick the hood by grabbing the front of it and wiggling. Removing the bumper gave me enough room to grab it that way.