45 replies to this topic

[skypig]

I’m really hoping you guys can help me here. I’ve acquired a 1986 CRX HF that’s in great shape and runs really well. It has no rust, the frame is straight, all of the vacuum hoses (lots and lots of them) are in great shape (no leaks that I can find), and it is all original as far as I can tell. It has the federal emissions (KA) carbureted setup. I’m trying to restore this vehicle to use as a gas saving commuter and it needs to pass California smog (enter your sympathy noises here)  . I took it in for an initial smog test to see where it stood. Well, it failed miserably with high NOX (as in gross polluter). I’ve started troubleshooting and find that I need an oxygen sensor; the 5 wire, impossible to find one, with a Honda part number of 36531-PE1-A02. Apparently this is a wideband sensor. I’m not seeing any voltage change when I connect to it and disconnect vacuum lines to cause the engine to change its air/fuel ratio.

 

I have had zero luck in finding this part and hope to find suitable substitute, short of a swap if I can help it. I am looking at the possibility of using a PLX or Innovate wideband sensor but it looks like I will need to reprogram the ECU to do this. Does anybody have any info regarding this on these cars? My ECU part number is  37820-PE1-661, and I can find no information regarding it. I have found the lists of Honda ECU part numbers and all of the lists I have seen don’t even go back as far as 1986.

 

Is it possible to chip this? If so, please, educate me. Or, could I put in the wideband O2 and bypass the ECU altogether? There is no CEL on the car (OBD0) and I have found no way of getting any codes from the ECU, so I don’t seem to have to worry about that. There are some LEDs on the ECU but I have found no way to get them to divulge any information.  

So…does anybody have any options for some different routes I can take to get this thing to pass CA smog get on the road? I’m open to any ideas as I’m new to this. I’m mechanical enough to do pretty much anything, but I did not get this to learn to do a swap, although that may not be out of the question, especially if I could get someone with experience to help out. That could be very interesting, but I digress. I was hoping to rebuild and fix things on it that need work and be able to drive it back and forth to work. I’ve become rather attached to this thing and really want to see it in use.

 

Looking for any and all ideas and options, please help.      

 

Thanx,

Biff

[gtpilot]

The blinking LED on the ECU is the code for the errors... a long blink = 10 and the number of short blinks you count.  So, one long and three shorts is 13...then a pause and another code could be presented if there is more than one failure.  What numbers are you getting?

 

http://www.oreillyau...02205&ppt=C2179 - they show they have the 02 sensor.

 

Kirk

[skypig]

Unfortunately, that O2 sensor won't work on this model. Because it's a federal emissions type it must have the 5 wire wideband O2 sensor.

 

The LEDs don't do anything. I've turned the car on and off, and run the car with the ECU sitting on the floor next to me, and the LEDs do nothing. Is there a set of pins I need to short, or a certain procedure that needs to be done to get the code out of the ECU?

 

I've been looking for info on reprogramming the chip on the ECU and I'm not finding any info that indicates I can do anything with this ECU.

 

Biff

[cbstdscott]

I am going to guess that if you need an new O2 sensor you are also going to need a new catalytic converter as well. When one fails, the other is soon to follow.

[skypig]

That's probably a true statement, but I don't think these are three way cats, so I don't know that they do much for NOX. I'm hoping that if I were to get the O2 sensor and it gets the A/F ratio correct then things will fall more in line emissions wise. As it is it passed everything except NOX.

 

I'm wondering if the O2 sensor is putting out a signal such that it keeps the engine running on the lean side. It does tend to get hot if left to idle for a while. I was going to replace the thermostat for this. No heat issues driving with the extra air flow. This just came to mind. I should try running it without the O2 sensor connected (open loop?) to see if the temp changes any. Could the O2 sensor be putting out a signal such that the ECU tells the engine to run a bit lean, causing a hotter burn, thereby increasing NOX? At least it's something new to try.

 

After I had the smog test, I did have to retard the timing, and I replaced plugs and ran Seafoam through it as it looked like there was some carbon buildup in the plug chamber when I replaced the plugs. I just don't know that retarding the timing and cooling the engine can eliminate enough NOX to pass. Believe me, I would be one very happy, but dumbfounded dude if it did work.

 

The more I research though, the more it looks like this may be a basket case. Even a swap sounds like a more than major undertaking since it's a carbed engine. I'll see what happens after I try running with the disconnected O2 sensor and replace the thermostat. I can try another smog test to see if I have made any changes.  

 

Any other ideas, please throw them out there.

[copjoe]

Try searching that part number on ebay it comes up with a couple of diffrent ones ,,,, nut sure if any are the right ones for you though.

[skypig]

I've done the ebay thing searching in many different ways. Apparently it's a very specific O2 sensor. Plus, this sensor is a different size. It has a smaller threaded body than the typical.

[asianflava]

One of the pitfalls with having these old cars... discontinued parts.  It's odd that they discontinued this part since it's a consumable item.  Have you tried e-mailing Bosch (or other O2 sensor suppliers) asking if they have an equivalent or an option for replacement?  It wouldn't hurt.

 

-Good luck   

[skypig]

No, I've not gone that route, but it sounds like a viable plan. Sure as he77 can't hurt. I'll draft up a form letter of what I'm looking for and give it a whirl. Dang, now I'm getting my hopes up again. This is the roller coaster ride from he77.

My wife actually said get another engine for it. The rest of the car is in good shape and I can keep it up mechanically. Anybody know of where I can get a d15z1 and someone in Sacramento CA area that can help with a massive swap?

[PuddleSkipper]

I'm selling a spare D15z1 swap for $800 in the Portland area, 120,000 miles. Chances are once I figure out my D15Z1 swap I can help you with yours, or maybe even make you a harness based on what I did to my own car. Come on up, your only ten hours away 

http://portland.crai...3794411237.html

 

Not sure about emmissions in your state, this isn't a CA car which has separate emissions requirements.

[CRXer87hf]

Are you telling me they expect you to pass smog in a carbed '86 that didn't even come with a cat? BULL SH*T!  This is why I'll never live in California.  I'm dealing with emissions now with a turboed vtec honda in Georgia.  Major PITA. To start, the ECU on a 86 CRX HF does very little at all.  Are you sure the car even had an 02 sensor from the factory?  I'm pretty sure it didn't, so if you're going to run a factory exhaust, you'll have to weld in a bung somewhere and mount an after market wide-band 02, however, it won't communicate with the factory ECU.  You're talking serious mods here.  I would suggest a wide band hooked to a air/fuel gauge, or laptop hookup with software.  

 

http://www.mvpmotors...SubFolderID=928

 

Basically, that will help you tune the car, but it'll boil down to some manual carb tuning.  I would start by making sure the car is burning as much of the fuel that is going into the cylinders, then you can adjust the rest with timing.  They will be probing the exhaust to you'll want to install an aftermarket cat.  Put one on before you tune the car because there will be a change in back pressure with the cat.  The issue with that is finding an aftermarket cat that supports the factory exhaust size, which is TINY.  I think it was less than 2".  

 

I don't know how insane California's emissions test are, but there's not much else you can do to get it to pass.  Good luck!

[PuddleSkipper]

This is why I'll never live in California. 

 

I agree, especially since they banned ZC's. I don't see any reason why a D15Z1 O2 sensor would not work. You should be able to see where the wires go for the HF O2 sensor go and see if they do the same stuff that the VX one does. You'll have to change the plug though to an OBD1 8 pin plug. The VX had 7 wires going to it but there is a sensor in the connector somewhere so that only 5 wires go from the connector to the O2 itself. 

[skypig]

As far as I can tell this is all stock. It's just a very weird version of this year and model. My understanding is that it had a wideband O2 from the factory and a lean burn feature on the federal version, but I think the CA version eliminated the lean burn for emissions. And it does have a cat, I just don't know if it is working. I've seen them in junk yards with and without an O2 sensor, but they all had a cat. I would like to get the O2 sensor sending the correct info to the ECU so the A/F ratio is correct. Then I'll smog it and see where I am at. And yes, the pipes are small, 1.5 inches I believe.

I've considered the aftermarket wideband route but I will need to figure out how this output can be used to control the A/F mixture since the signal will not mean anything to the ECU.

I'm new to most of this engine tuning stuff and Honda's in general. Boy am I getting a crash course.

What's a ZC?

I'll keep your engine in mind PuddleSkipper. At this point, there's no telling what will happen. This started out simply as a way to try to save some money (about 7 bucks a day on fuel) by buying a cheap economic car, put a few hundred bucks into it and enjoy the ride. Now...???

[PuddleSkipper]

A ZC is the JDM version of the D series. It's a DOHC D series though  If you go the Vx route you'll have to convert to FI or fuel injection. I wouldn't mind if you dragged you car up here after I'm done with mine, I may get bore 

[CRXer87hf]

As far as I can tell this is all stock. It's just a very weird version of this year and model. My understanding is that it had a wideband O2 from the factory and a lean burn feature on the federal version, but I think the CA version eliminated the lean burn for emissions. And it does have a cat, I just don't know if it is working. I've seen them in junk yards with and without an O2 sensor, but they all had a cat. I would like to get the O2 sensor sending the correct info to the ECU so the A/F ratio is correct. Then I'll smog it and see where I am at. And yes, the pipes are small, 1.5 inches I believe.

 

Wow, I had no idea they made special models with an O2 sensor and a cat... you're not the only one learning here.