Smog Failure/O2 Sensor Question

Clinton

Power Blue!!
Apr 8, 2005
63
0
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38
Sacramento, CA
Hey guys,
My '89 MkIII has decided to fail the smog test. After I ran it and got the fail, I noticed that it was running rather rich -- smelly exhaust. First thing I thought to check was my O2 sensor, so I looked it up and went and grabbed one listed as appropriate for my year (Bosch 1-wire sensor) but when I got it home and went to put it in, the currently installed O2 sensor is some peculiar 3-wire deal with a different connector. I can't seem to find any listing for it anywhere for (what I thought was) a stock '89T. Anyone seen something as peculiar as this before?

Also, are there other simple things I can check to see why my car is running really rather rich, where it didn't before? I think I'm getting around 10MPG tops as it is right now, and in addition to not passing smog (and thus running around on expired tags) I'm getting hit in the wallet for petrol at this level of consumption. What can I check/do to make my car happy again? I've been trying to find some sort of dodgy russian smog shop or something to be able to at least get current tags.

Thanks!

CCC`
 

Nick M

Black Rifles Matter
Sep 9, 2005
8,873
37
48
U.S.
www.ebay.com
You could have a small exhaust leak. That would make your oxygen sensor send a lower reading, indicating a lean mixture to the ECU. The ECU would of course richen it.

No, it isn't peculiar to have a 3 or 4 wire at all. The extra wires put current into the element so it warms up faster.

Make sure the car is nice and hot, so the cat is lit before you test.
 

Clinton

Power Blue!!
Apr 8, 2005
63
0
0
38
Sacramento, CA
as far as I know, I got the turbo sensor. Autozone/Kragen lists a one-wire sensor for the supra turbo, and no three wire sensors to be listed there. I'm kind of baffled as to why I have some sort of peculiar O2 sensor, and am unsure if it's failed or not. My car did sit mostly unstarted, unmolested, and unused for about eight months while I was in the process of relocating, and fired up fine from the start again, but now seems to be running hella rich. I've been told I could have a dirty MAF, any easy way to clean that beast without destroying it?

Cheers!

CCC
 

Zumtizzle

Can't Wait to Be King.
Oct 21, 2006
2,825
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36
Sac-Town, NorCal
Clinton;1038178 said:
as far as I know, I got the turbo sensor. Autozone/Kragen lists a one-wire sensor for the supra turbo, and no three wire sensors to be listed there. I'm kind of baffled as to why I have some sort of peculiar O2 sensor, and am unsure if it's failed or not. My car did sit mostly unstarted, unmolested, and unused for about eight months while I was in the process of relocating, and fired up fine from the start again, but now seems to be running hella rich. I've been told I could have a dirty MAF, any easy way to clean that beast without destroying it?

Cheers!

CCC

Maf isn't a issue. It works from vibration.

http://www.partsamerica.com/Product...IE&MfrPartNumber=FE80533&PartType=291&PTSet=A
kragen does list a 3 wire sensor, they're just all fucking idiots.

Check the hose going to the turbo to intercooler, does it have any leaks?

rockauto has the o2, or hell get it from the dealer (I/Dad did many times.).

I'll sell you mine, which is ready to go into the car for 75 bux, and is brand new + your old one.

(I'm trying to make a few bux, but if you don't need it right away i know other options)
 
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Clinton

Power Blue!!
Apr 8, 2005
63
0
0
38
Sacramento, CA
Zumtizzle;1038189 said:
Maf isn't a issue. It works from vibration.

http://www.partsamerica.com/Product...IE&MfrPartNumber=FE80533&PartType=291&PTSet=A
kragen does list a 3 wire sensor, they're just all fucking idiots.

Check the hose going to the turbo to intercooler, does it have any leaks?

rockauto has the o2, or hell get it from the dealer (I/Dad did many times.).

I'll sell you mine, which is ready to go into the car for 75 bux, and is brand new + your old one.

(I'm trying to make a few bux, but if you don't need it right away i know other options)


Wher'bouts in Sacramento do you live, and do you have any recommendations on smog places to take it to? :p I'll probably have a poke around under the hood this weekend. I've been outta town the last couple weeks, so haven't had a chance to examine why I can't get the damn thing to pass smog :p

Anyway, yeah

Cheers!

CCC
 

Zumtizzle

Can't Wait to Be King.
Oct 21, 2006
2,825
0
36
Sac-Town, NorCal
Clinton;1038235 said:
Wher'bouts in Sacramento do you live, and do you have any recommendations on smog places to take it to? :p I'll probably have a poke around under the hood this weekend. I've been outta town the last couple weeks, so haven't had a chance to examine why I can't get the damn thing to pass smog :p

Anyway, yeah

Cheers!

CCC

On Folsom Blvd, In Rancho Cordova; right next good year, and Autozone.

I'm in Rancho Cordova.

Let me know on the o2! The one wire will work, make sure it goes to the right wire. ;)
 

Clinton

Power Blue!!
Apr 8, 2005
63
0
0
38
Sacramento, CA
jetjock;1038317 said:
1) The 3 wire is not peculiar.

2) The 1 wire will work if it can be mounted.

3) I see little point in asking for help with an emissions problem unless you post the results up.


1) Apparently not, it just doesn't appear in the parts catalogues available at our fine chains of automotive supply shops, so thought it was rather odd.

2) How exactly how would I go about mounting it? are there guidelines and such anywhere? I didn't really find anything in the TSRM

3) I fear that I've mislaid my emissions test results at the moment, but I know that I failed on %HC, and CO. My levels were 5-12x the legal limit, and now I notice that my car is running pig-rich. Fuel consumption is really off the charts.

CCC
 

ninja6o4

New Member
Apr 29, 2008
57
0
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Surrey, BC
Really sounds like O2 sensor to me if you're pounding that much fuel out the back. Return the 1 wire and get the right one as stated above...