Hello everyone. I hope all is well in the 2nd gen world!
I have a 91 RS with a b17 swap. Running rywire jumper harness for 0bd0 to 0bd1. Well my o2 sensor plug (from rywire) was laying on my header, and completely melted. I am throwing a code 43, idling high and getting poor gas mileage (200 miles to a tank).
Anyway I went to rewire the o2 sensor, only to find that I have no idea which wires go to which. I know that on my denso O2, blue is ground, white is signal, and the two black wires are heaters. But the wires I have coming from the ecu are purple, grey, yellow and brown. I have been searching everywhere, contacted rywire and have not heard back. Before I go and solder a new plug on, want to make sure that I get it correct. Any input would be much appreciated!
I may be getting close to the answer… just one more loose end.
I tracked the wires to the ECU, and found this.
Purple wire-D22 (ground)
yellow wire-A25 (power IGP2)… Is this one the “signal wire”/???
Grey wire- to be determined, I am at work only had time to trace 2 of the 4.
brown wire-TBD stay tuned (pun intended)
Maybe someone knows, if they have a Rywire harness, but those colors are specific to his harness and don’t match the factory colors. The quickest way to accomplish what you are trying to do is to simply use a mult-meter to check continuity back to the ECU and compare with a pinout diagram. What’s the actual connector look like? Even if it’s melted you should be able to see which wire went into which pin location on the connector and that should also be all you need to get it wired up correctly. I’m pretty sure Helms even has a page showing the connector with pin locations - should be in the fuel/emissions section IIRC.
You are right about it being a specific harness, Colin. Here is what happened exactly. The connector melted about 8 months ago. I was able to do what you said and look at the connector to discover which goes where. But instead if soldering them up like I should, I twisted them together and taped em up real well. I wanted to make sure I had it right. I forgot about it and recently did the rear main seal, so was moving things about quite a bit. At this point the wires came apart. It’s a very strange situation and completely my fault. But as soon as I can discover the correct wiring I’m soldering them for good. I even have a new connector. Anyways I have traced the wires to the ecu, and with some pinout pictures online discovered which is which. Thanks as always Colin
[QUOTE=pkda9;2335048]
Now to just pick up a soldering gun and make it permanent.[/QUOTE]
If you plan on doing some more wiring I suggest getting some OEM pins. I bought some from CJ’s Harnesses (or was it cycleterminal.com?) and now if possible I always just crimp on a new pin so that there’s no soldered connections needed.
So I thought I had figured out the issue. After I soldered the wires the CEL went away, and stayed off for about 3 days. Then it came back on! I am so frustrated with this code. Now Im thinking multiple issues? Some people have told me to check gas cap, so I will be picking one up this week. I have noticed it doesnt “hiss” when I unscrew it anymore. Also fuel pressure regulator (is there a test for this?), injectors, and one of my friends said he cleaned out the entire fuel system and that solved it for him. Any other tips on code 43??:bang::down:
Quadruple check your wiring. I’m 90% sure, and colin can back me up on this one, that one of the O2 signal wires is shielded to avoid interference.
Also, is this a new O2 sensor or an old one? Never hurts to have a new O2 sensor.
Next up, a new fuel filter if you haven’t yet. There’s a way to put a fuel pressure gauge on it while you’re at it. Will come in handy one day anyways. The gauge I bought was Marshall Instruments MS00100 Fuel Pressure Gauge. $20 and endlessly valuable when troubleshooting.
Hey thanks! When you say the wire is shielded what does that mean? And yes I replaced the sensor, figured it couldn’t hurt. I plan on getting in there soon to double check everything, and label the wires this time. I did replace the fuel filter about a year ago. I think it is idling a bit rough. I thought it was the motor mounts ts (hasport 62a) but it seems rough to me. So maybe injectors are at fault as well. I’ll keep it posted thanks for the tips
By shielded I mean that the wire has a wrap around it that helps it avoid interference from other electrical sources around it.
If you’re testing injectors, without getting too technical, you can unplug one at a time and see if the car doesn’t change much when one is unplugged. If there’s someone around you who cleans and tests them, I’d highly recommend it.
