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Failed Smog now what??

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Old Aug 22, 2012 | 02:12 AM
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Year: 1991
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Default Failed Smog now what??

I took my 91 XJ Limited to get smogged and now is a gross polluter.
Evap and visual passed but the emissions came out like this:

-------%CO2 - %O2 ----- HC (PPM) ----- CO% ------NO (PPM)
__ RPM MEAS- MEAS- MAX/ GP/ MEAS- MAX/ GP / MEAS -MAX/ GP/ MEAS
15 1619 10.7 - 0.1 - 86 / 310/ 180 - 0.73/ 2.03/ 6.38 - 711/ 1800/ 118
25 1592 11.5 - 0.0 - 103/ 260/ 175 - 0.93/ 2.23/ 4.99 - 613/1600/ 114

Any ideas would help. Also I noticed oil on my air filter coming from the tube that connects the valve cover.
Thanks

Last edited by taxidave; Aug 22, 2012 at 12:12 PM.
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Old Aug 22, 2012 | 09:43 AM
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First things that come to my mind, internal oil leak (AKA you're burning oil), and/or a bad Cat.

That oil in the filter is a faulty PCV valve, shouldn't affect your emissions. But its worth fixing if you can find the parts.
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Old Aug 22, 2012 | 10:45 AM
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Originally Posted by 1976Mustang
First things that come to my mind, internal oil leak (AKA you're burning oil), and/or a bad Cat.

That oil in the filter is a faulty PCV valve, shouldn't affect your emissions. But its worth fixing if you can find the parts.
When I recently replaced my rusted springs, I took off the back part of the exhaust at the flange at the cat for some room to work. I didn't replace the gasket. Would that have an effect?
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Old Aug 22, 2012 | 11:58 AM
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Shouldn't, since they test the exhaust coming out of the tailpipe. But i would replace that gasket anyways, just as a safety thing.
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Old Aug 22, 2012 | 12:11 PM
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I just did an OBD I scan it it showed
"51 - Sustained lean air/fuel ration condition detected in o2 sensor bank 1 position 1.
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Old Aug 22, 2012 | 12:17 PM
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Originally Posted by 1976Mustang
That oil in the filter is a faulty PCV valve, shouldn't affect your emissions. But its worth fixing if you can find the parts.
CCV****

Originally Posted by taxidave
I just did an OBD I scan it it showed
"51 - Sustained lean air/fuel ration condition detected in o2 sensor bank 1 position 1.
Hmm you should replace that gasket. You may have a small exhaust leak, causing the air/fuel ratio to be thrown off. Ever replaced the upstream o2?
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Old Aug 22, 2012 | 12:19 PM
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replace O2 sensor and see if that helps.
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Old Aug 22, 2012 | 12:25 PM
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Originally Posted by 1996sportXJ
CCV****
We know it's a CCV, the parts stores call it PCV.


Originally Posted by 1996sportXJ
Hmm you should replace that gasket. You may have a small exhaust leak, causing the air/fuel ratio to be thrown off. Ever replaced the upstream o2?
Will replace the gasket I haven't replaced the o2 sensor yet. I already ordered the NGK 23023.
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Old Aug 22, 2012 | 12:28 PM
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Originally Posted by taxidave
Will replace the gasket I haven't replaced the o2 sensor yet. I already ordered the NGK 23023.
Good deal, that might very well be your whole issue right there.
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Old Aug 22, 2012 | 12:36 PM
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Also the CCV elbow that goes to the intake (the elbow closer to the firewall) looks pretty bad too. It appears to be a different elbow than the front one. The parts stores only list the one for the front.
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Old Aug 22, 2012 | 12:40 PM
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Yep, it's supposed to be that way. The rear is a dealer only part I hate to tell you.
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Old Aug 22, 2012 | 12:55 PM
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Originally Posted by 1996sportXJ
Yep, it's supposed to be that way. The rear is a dealer only part I hate to tell you.
I wonder if it will cost more than the O2 sensor I'm getting from Amazon.
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Old Aug 22, 2012 | 01:07 PM
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Haha nah man it won't be. It'll cost you $5 tops I would think
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Old Aug 22, 2012 | 01:18 PM
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Man I'm glad we don't have testing.... yet
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Old Aug 22, 2012 | 01:40 PM
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Originally Posted by 1996sportXJ
Haha nah man it won't be. It'll cost you $5 tops I would think
That'll be a first. I bought a pinion nut that cost more than the impact socket I bought to put it on.

Update: I replaced the front CCV elbow, air filter, cleaned the air box and cleared the codes. I took it for a drive (non-freeway) to Starbucks and back and the scanner now shows no codes, all systems running properly.
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