obd to obd1 conversion with check engine

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sleeper88

My mom thinks i'm cool
I just did my obd to obd1 conversion today, i started up the car and there was a check engine light, the codes that came out was 20(Electrical Load Detector defective circuit or unplugged / defective sensor) and 41(Primary Oxygen Sensor - Heater circuit malfunction). I have a universal ngk o2 sensor with two white, one gray and one black wire. I've tryed switching the two heater wires but still no change. I've hooked up the v-tec,o2 sensor, and distributor. I'm running a p28. I dont think anything else needs to be hooked up, the o2 sensor is brand new too. So if you guys could help and shine a lil light on my lil problem. Thank you
 
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eld is in the dist. wiring. you probably screwed up a wire there. double check it.
we have pinouts in the reference section, so verify all your wires. you probably just ran a couple things wrong.
 
Could it just be the dist.? b/c i bought the obd to obd1 dist. adapter plugs. The obd1 dist. that i put in the car for the conversion came along with the car with a broken cap,( a extra cap came along with the car for that dist.) So i just put the new cap on the dist. and put it on the car. Is there a chance that the dist. could of bin bad from the start and thats why its doing this? Plus i got it running today but all it will do is idle but it sounds like its missing and when i try to open the throttle it just dies and then i cant get it started again. It just turns over and shuts off like there is spark for a second and then nothing.
 
Im having the same issues with my ls. I just did the same swap as you three weeks ago and was throwing like 4 codes when I started. Im down to one now. Sounds like you might need a 4 wire o2 sensor. Ive changed my distributor and that didnt fix the eld code (20). the problem is the 91 doesnt have an ELD. How am I supposed to fix the eld code. Need help with the ELD.
 
also the injetors for the obd0 have a resistor box on the drivers side near the firewall. it has a green plug. cut the wires on the smaeside as the resistor box and twist the wires together. now the obd1 injectors have the 12 volts they need to work instead of the 5.5 volts you get with obd0
 
Well i'm still using the obd0 injectors. I got my new distributor today but its still throwing the 20 code, and for some reason its not throwing the 41 code anymore, So all i have to do is work on code 20. I just cant figure it out, everything is just plug and play. Everything was working fine before the conversion and now this.
 
does any1 have a full ecu obd0 wiring diagrams for ecu. also how does the ecu get power from the battery ??

cheers in advance
 
man im having the same problems with mine. but my two codes were the IAC (code14) and that damn code 20. the car had no problems before i did the swap except the engine leaked mad oil. I changed everything, Alt. dist. still the same mess. Let me ask you this does your engine light come on immediately or does it take like 5 or so seconds to come on.
 
how do you kno what codes are for what probem and is it alot of work to do a obd0 to a obd1. I have a 88 crx and i want to put a b16b on it but i dont know alot about the conversion yet.
 
Sorry i haven't posted in awhile. The check engine light comes on but like all check engine lights when you check them have like a 5 second pause between them. But no i couldn't figure out code 20. I really dont want to cut any harness b/c thats why i bought the adapter harness. So it could be as clean as possible. Instead of trying to figure it out at the moment i just changed it back over to obd0. I'm not a wizz at wireing so i might get somebody to look at it b/c they would prolly see right away whats wrong with it. Other then me take forever trying to figure it out. I wished i could of gotten it working though. Did you figure it out yet?
 
does any1 have a full ecu obd0 wiring diagrams for ecu. also how does the ecu get power from the battery ??

cheers in advance
Here's a gif of the 1991 pr4 ecu connections. Hope it helps.
 

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You sound just like me because thats what im about to do is just switch it back to obdo to see if that works. Inside the repair manual i got the 91 doesnt even have an eld but the 95 does. So im confused and tired of messing with so back to obd0 seems the best thing to do
 
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