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Discussion Starter #1
Hey guys,

Argh...the numbers from my most recent FAILED emissions test are:

HC Limit = 64; HC reading = 107 FAIL
CO% Limit = 0.35; CO% reading = 0.23 PASS
NO Limit = 485; NO reading = 674 FAIL

All the curb data were fine.

My previous numbers were way lower in all categories (I passed last time).

I just checked my ignition timing and it is at 11 degree before TDC.

I had to replace my VCGs because I was burning tons of oil. I figured this destroyed my O2 sensors (which I will be replacing next week). Do you think I need to replace the cat too?

My mechanic says to do the O2 sensors and drive the car for 7-10 days - hopefully this will clean out the cat a little.

Anyone have any other thoughts about this? Could there be other things at work here?

Thanks in advance.
 

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ive been a vehicle inspector for years check it out hc's are in the oil if your oil hasnt been changed then hc's will be high if you have been burning alot of oil then there is proably oil (or hc's) still burning in the exhaust system

NOX-nox could be a few different things EGR, CAT,O2s,or TIMING,nothing else so timing is close i would check and see if the o2s have been replaced if not it wouldnt hurt but the cat there is a way to check it take the pipe from the back and feel how much pressure you have and then put it back and do the same for the front if rear has less pressure than the front then the cat is clogged and need replacing.EGR could be cleaned by scraping or tb cleaner.
 

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Have you had your timing belt replaced recently? I have heard a few of those jobs getting done improperly, resulting in failing emissions, although the car seems to run fine.
 

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Discussion Starter #5
I had it replaced when I bought the car in 2001 when it had 114 kms on it. Now it has 150 kms. I don't think it needs another replace...

I just hope it was done properly...
 

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the easy fix ---just to get it on the road untill you fix the problem

go to canadian tire and pick up a bottle of " guaranteed to pass" stuff and follow the box... i used it on mine after it failed and it passed with out any problems the second time around, it takes some time and a few tanks of gas but it got it on the road...
 

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cant you use lower octane to burn more complete? someone told me that and it makes some sense to me. but i aint sure
 

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Discussion Starter #9
Hey guys,

Just to finish up this thread.

I replaced both O2 sensors with Delco OEM ones and swapped my cat for a high-flow Catco one.

This was my new data:

HC Limit = 64; HC reading = 64 PASS (God this one was close...)
CO% Limit = 0.35; CO% reading = 0.15 PASS
NO Limit = 485; NO reading = 401 PASS

All the curb data were still fine.

Hope this helps anyone with similar issues.
 
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