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Help won't pass smog

turkeyassassin

NAXJA Forum User
Location
Apple Valley, Ca
Well I was finally able to get another XJ and any help would be greatly appreciated. Here's the situation 92 with the 4.0 and the following items have been replaced manifold, cat, and muffler. Attached is a picture of where it failed. Thank you
 
What are the rest of your readings. Usually a fail will result in several readings failing. Could be your marginal with not having your motor good and hot before test. I get out and run around and blow it out after adding a bottle or 2 of Heat/yellow bottle. Then I go test. I only have a sniff test here in Oregon.

You must pm me your procedure for adding pics that show up in post. I been around here since 2003 and still don't know how, I screw it up some how.
 
High Nox means the the cylinders are hotter than they should be and typically means a lean condition. Test/check, possibly replace your O2 sensor. Also, do the same with IAT (should be towards the rear of the intake manifold and have a 2-pin GM connector) and CTS (driver side lower part of the engine block, same 2-pim GM connector. Since you replaced your manifold, check for vacuum and exhaust leaks. Specs for what the sensors should be around. Pretty sure lunghd.com has some of them as well.

AS for posting pics upload your photos, resized correctly preferably, to your favorite hosting site. Then use the link in between the image code

For example,
url]
(no spaces in between the code and web address) if it works correctly then your picture will show in post. If not, then something went wrong.
 
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The O2 sensor has to be really broken for it to throw a code. The sensor changes resistance according to air-fuel mix, and it can easily report the wrong values and still appear to be operational.

Another thing to do is run some fuel system cleaner through a full tank of gas, in case you have a gummed injector that is restricting flow.
 
I'm currently running a bottle of SeaFoam in a fuel tank and have heard it's not a good idea to have a smog done while running such things in your fuel. Does anyone know if that's true?
 
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