86surfwagon Posted December 30, 2006 Share Posted December 30, 2006 I am lost and need a little assistance, and i know most of you will know exactly how to solve my problem! I am missing the wiring for my 02 sensor on an 86 gl wagon..... it has been ripped off of the sensor and is probobly burried under a lot of mud in a field somewhere. I put 2 new cats on last summer and would like to further remedy the emmission controls etc by fixing my 02 sensor. Does anyone know the typical routing for these wires? where is the ecu? how much information is really shared from the sensor to the carburator? My engine runs fine but i think a functioning sensor could improve my fuel econcmy and maybe give a bit more power? if someone knows i would be greatful!!! thanks champ Quote Link to comment Share on other sites More sharing options...
mikeshoup Posted December 30, 2006 Share Posted December 30, 2006 Is this an SPFI or Carb'd motor? If its Carb'd, is it a feedback model (IE: does it have CA emissions on it)? In other words, you sure you're supposed to have an O2 sensor? Otherwise, the ECU will be under your dash, below the steering column. Quote Link to comment Share on other sites More sharing options...
86surfwagon Posted December 30, 2006 Author Share Posted December 30, 2006 Is this an SPFI or Carb'd motor? If its Carb'd, is it a feedback model (IE: does it have CA emissions on it)? In other words, you sure you're supposed to have an O2 sensor? Otherwise, the ECU will be under your dash, below the steering column. supposedly this is a feedback carb, but this is the 3rd engine in the car, and the last motor came from japan about 3 years ago... i have had trouble with other parts not matching up too, ie belts! if there is no ecu should there be no o2 sensor? the original cats had an sensor installed so i am asssuming that there should be one.... Quote Link to comment Share on other sites More sharing options...
Phizinza Posted December 30, 2006 Share Posted December 30, 2006 I'm not real smart on computer controlled engines but I don't think a O2 sensor could help a carb in any way.. Or could it? Quote Link to comment Share on other sites More sharing options...
daeron Posted December 30, 2006 Share Posted December 30, 2006 okay, GD needs to see this thread.. I have never seen the feedback carb (honestly, rarelly seen the stock hitachi) but my understanding is the feedback carb has a mess of wires and sensors, whereas the non-feedback carb is a carb. it has vacuum hoses, and a couple of fuel lines. the feedback carb was NOT very typical. However, it did use an o2 sensor as part of its equipment. Take a good look at your carb and make an educated guess.. or search "feedback carb" and the name GeneralDisorder, in the Older Generation forum. I know he has posted alot of info about it, because he is a pretty knowledgable guy and has had a run-in with one. I'll let you know right now he didn't care for it, but he has made posts describing the difference between the two before, and maybe even with pictures. Also, watch the similar threads feature at the bottom of the page, this crapuretor comes up alot :-p Try editing your original post to include "feedback carb" in the subject line. The good news is, if you DONT have a feedback carb, you dont need an o2 sensor. the long term advice is going to be scrap it and install a weber. that seems to be consensus, for the most part. Quote Link to comment Share on other sites More sharing options...
86surfwagon Posted December 30, 2006 Author Share Posted December 30, 2006 wow thanks for all the advice.... especially in the technical parts of the forum, i see it can be a powerful tool if used for good so im thinking that my carb is NON feedback since i recently did the intake gaskets and all the little *************** coolant hoses that route around the carb and found no such rats nest of wires and sensors.... here is why i was thinking it needed the sensor. i had to take the beast through emissions this summer, a nightmare long story short i failed the first attempt and in washington state you can get a waiver to be passed if you have a certified shop do X ammount of dollars work trying to solve the problem so i paid some guys at what i understood to be a reputble shop, while not my subie shop of choice, to do an analysis and they came up with this bs problem of needing to run new wires for the o2 sensor for my "feedback carb". however they were dumbfounded and could not find any wiring or the ecu and ended up billing me basically for printing out the harness diagram for the ecu and telling me good luck.... yeah not worth $150. so i had 2 new cats installed, $400 and was able to recieve the waiver, and come pretty close to passing, but i worried that in a couple years when i have to go through again the o2 sensor problem is goning to bite me in the rump roast sorry to ramble, its just a really lame complicated story so will the webber carb perform a lot better than the stock hitachi? i have herd this but never really experienced it for myself... thanks again Quote Link to comment Share on other sites More sharing options...
mikeshoup Posted December 30, 2006 Share Posted December 30, 2006 I think the Weber would. Preferable thing to do is an SPFI swap. I didn't write the article on it, but here it is: http://mshoup.us/docs/spfi_conversion_manual.pdf Its not too terribly difficult, and will probably run you in parts just as much as a weber would + the SPFI runs very clean and is super reliable. Quote Link to comment Share on other sites More sharing options...
NorthWet Posted December 30, 2006 Share Posted December 30, 2006 If you are having to pass emissions, unless you are prepared to reinstall the original equipment then you probably don't want to go with either the Weber or the SPFI conversion. (My choice would be the SPFI conversion. ) Quote Link to comment Share on other sites More sharing options...
mikeshoup Posted December 30, 2006 Share Posted December 30, 2006 If you are having to pass emissions, unless you are prepared to reinstall the original equipment then you probably don't want to go with either the Weber or the SPFI conversion. (My choice would be the SPFI conversion. ) You can make the SPFI look like original equipment, and there were some 86s with SPFI on it anyways. The Weber on the other hand would be hard to make it look like original equipment. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted December 30, 2006 Share Posted December 30, 2006 Weber performs a LOT better. And it should pass WA state emissions - other have done it. Sounds like your feedback system is pretty whacked out - three different engines..... too many cooks in the kitchen. I would write it off and do the Weber swap, or better yet the SPFI. Feedback EA82's need the ECU to power the fuel pump, so unless it's been wired around, you still have it under the dash. Here's my write up on the SPFI - it's geared to EA81's, but the only real difference is you wouldn't have to modify the distributor for your application. http://home.comcast.net/~trilinear/EA81_SPFI.html Generally the SPFI cheaper than a brand new Weber, and about the same price as a used Weber if you rebuild it yourself. The SPFI is good for about 2 MPG more than a properly tuned Weber, but doesn't require any tuneing, and generally has better driving charateristics, fewer problems, and just as much power. It's manifold flows better, and the SPFI engines were already rated at 6 HP more than the carbs, so it's quite a decent setup. You'll spend more time and likely more money trying to make the feedback Hitachi work than you will on a swap. And either way you go with the swap you will pass emissions, and be better off in the long run. The feedback Hitachi was one of the worst carbs the Subaru's ever came with - especially the EA82 version. Second only to the EA81 carter/weber single barrel feedback GD Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted December 30, 2006 Share Posted December 30, 2006 You can make the SPFI look like original equipment, and there were some 86s with SPFI on it anyways. The Weber on the other hand would be hard to make it look like original equipment. Not as hard as you think actually - cut out the bottom of the stock airbox, a couple bits from a coffee can, and some JB weld and all sins are hidden again. Take it back off when you are done unless you like it. With the airbox in place, it's real hard to see much of anything under there, and as long as it passes the sniffer, they won't even care. Besides that, some places don't even do the underhood inspection. Out of the 10 or so odd times I've taken a subaru through here in oregon probably 2 of them they actually lifted the hood. And even then they didn't know what they were looking at - marked down NA next to the air injection system just cause they didn't see a smog pump GD Quote Link to comment Share on other sites More sharing options...
GoldDiggerRoo Posted December 30, 2006 Share Posted December 30, 2006 The feedback Hitachi was one of the worst carbs the Subaru's ever came with - especially the EA82 version. GD I totally agree I wish you luck my friend, as I too have been stung by the feedback carb, on a EA81... but that's bad enough. If I ever ran into a EA82 with the feedback I would run for the hills. BTW, not sure if it'll help, but I can follow/photograph the o2 wiring for you, it's on an '88 Hatch, but I wouldn't imagine it would be much different, but in all honestly, I'd just go webber or SPFI. Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted December 30, 2006 Share Posted December 30, 2006 Yeah - my EA82 feedback sedan got a Weber after 5,000 miles of dinking with the feedback. There's a boost sensor on the passenger strut tower that's pretty much always bad, and cost's about $300 for a replacement. Plus it has the same problems as the rest of the non-feedback Hitachi's. Too small, vacuum secondary, and choke spring failure. On the plus side, I've never touched the ECU - I just removed the bulb for the CEL, and the ECU keeps the fuel pump running for me - that's it's only job now. Weber power is soooo nice. Freeway merging with a Hitachi is scary. GD Quote Link to comment Share on other sites More sharing options...
daeron Posted December 31, 2006 Share Posted December 31, 2006 Uhm, yah guys.. but.. wow thanks for all the advice.... so im thinking that my carb is NON feedback since i recently did the intake gaskets and all the little *************** coolant hoses that route around the carb and found no such rats nest of wires and sensors.... here is why i was thinking it needed the sensor..... He thinks he does NOT have a feedback carb. so the conclusion would be, no o2 sensor needed.. If you are having difficulty passing emissions, you may be having carb issues of many sorts, of which I am largely ignorant. A simple rebuilt stock hitachi carburetor would possibly fix these problems... but there are lots of reasons to fail emissions. One trick my dad used alot when we still had emissions testing down here was to run one tank dry (the dual tank conversion van was our problem vehicle) and put a gallon of denatured alcohol in it, switch over to the alcohol and give her a good hot burn out along a highway near the station, and come in for the test.. We ultimately had to replace the carb to get it to pass finally.. BUT in the end we ALSO determined that the people who had rebuilt/installed the longblock in rural NC had put the headgaskets on upside-down, or rotated 180*, or something along those lines.. (I only heard that part, I didn't see it for myself. My dad and brothers were doing the work.) Fuel additives to clean valve deposits can help as well. I'm sure others can tell you much more and in accurate detail than I. Just wanted to redirect the discussion Quote Link to comment Share on other sites More sharing options...
Gloyale Posted December 31, 2006 Share Posted December 31, 2006 Hmmm... unless your car is from CA or is a 2wd it will most likely NOT have a feedback carb. I say most likely because someone could have put the wrong carb on it in the motor swaps. Look at the sticker that has the vaccuum hose diagram and read the fine print. If it say's california in that fine print then you should have a feedback carb and ecu, o2 sens, etc. The shop probably had a generic service manual that doesn't specify that the feedback carbs where only on the CA cars and some early 2wds. No feedback, no O2 sensor or ECU. The ECU would be bolted to the bottom of the steering column if it has one. If there are just 3 unused studs there and no box it probably never had one. Quote Link to comment Share on other sites More sharing options...
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