Ok here is the deal Im building my own A/F guage for my 98 Civic EX. I have all the parts to do it except one chip and it is on the way in the mail. the question is what wire going into the ecu is the O2 sensor wire because I need to tap into it. Another question is what O2 sensor do I need to use because I plan on knocking my car down to an obd-I instead of an obd-II.

 

The front sensor. I am unsure of the wire color on your car. I may be the white with the silver band.


Jason

 

I hope you got your LM3915 chip for free at national.com, and at least 5 of them. Use the sensor wire from the front o2, as for color I am at a loss also. Are you going to the obd1 for more power, or are you planning to remove the cat? If you are just planning to remove the cat, there is a simple schematic for an o2 sensor simulator using a 555 chip. Very few pieces and it works like a charm. If you are interested in more do-it-yourself elec., I can probably help you out.... Vtec controller, shift-light.....

 

do it yourself shift light would be cool.

D

 

Yeah I have already removed the converter and placed in a test pipe and I plan on making it obd-I for more power and it is easier to tune an obd-I than that stupid obd-II. I ordered my LM3914 chip from Radio Shack havent got it yet but I was told through an email from someone that National they didnt have that deal anymore where you could get stuff for free or for a lower cost. Why do I need 5 or more LM3914's? and if you want you can send me some more do it yourself elec. stuff.

 

They do give out free samples on the parts with a free samples button on them. Why would you need 5, you may want to sell a couple for 10-20 bucks and they'd be more accurate than the ones that are off-the-shelf. You could also make a knock sensor meter, dancing lights to music like a cheesey display of some sort, so that if you mess up one you have four more to play with. I have been getting free samples from national on an almost weekly basis for a couple of months, since dustin told me about the free samples thing. You would want to get free LM3915Ns, some op amps and some frequency to voltage converters for shift lights. Get dual and quad op amps, all free from national.com. I will post some schematics for us all.....Actually, most of them are on the data sheets at national for our exact applications. How are you doing your AF meter, by the way? When you do it, you'd want the low reference setting at .7 volts and high ref. at 1.0 volts. It would give more resolution in the stoich to rich side. You don't want to know how lean you're running, you'll be melting something in the engine if your af meter goes below .6 volts, too lean....