fail smog test.

1994 FORD AEROSTAR
320,000 MILES
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SANDY MENDOZA
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first smog test failed on the 15 mph at a reading of 799. one of my friends said it was the egr value. another friend said that there is no egr value on my aerostar. he replace the pvc value on it. took it back to re-smog and now both the 15 and 25 mph failed. on the 15mph reading it said 701 and on the 25mph it said 585. does the 1994 aerostar 3.0 have egr value? is it something else. please help me

just had the tune-up and the tran fluid change on it it run like a champ
Oct 18, 2011 at 11:45 PM
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ASEMASTER6371
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what reading?? you have hc co and nox whcih one??

Roy
Oct 18, 2011 at 11:47 PM
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SANDY MENDOZA
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it on the no ppm
Oct 18, 2011 at 11:52 PM
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SANDY MENDOZA
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it is on the no[ppm] reading on the smog test.
Oct 18, 2011 at 11:54 PM
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ASEMASTER6371
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i would look more toward the cat conveter. that is what breaks down the nox and eats it up.

Roy
Oct 18, 2011 at 11:58 PM
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RASMATAZ
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Could be the EGR, 3-way converter ,or a computer controlled system that stays in the open loop mode-
Oct 18, 2011 at 11:59 PM
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SANDY MENDOZA
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HOW DO I FIND OUT WHAT NEEDS TO BE DONE WHEN TWO OF YOU GAVE ME TWO DIFFERENT ANSWERS!!!! IS THERE A TEST THAT CAN TELL ME EXACTLY WHAT IS WRONG WITH IT
Oct 19, 2011 at 12:23 AM
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ASEMASTER6371
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thats what a shop is for. they can do the diagnostic and tell you exactly what the issue is.

we are both on the same track, not too different. raz was telling you all the possibilities and i was telling you my expierence in the repairs I have done.

Roy
Oct 19, 2011 at 12:34 AM
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RASMATAZ
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3.0 liter has no EGR valve-lean towards the C/Converter
Oct 19, 2011 at 12:36 AM
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RASMATAZ
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Let us know what's going on
Oct 19, 2011 at 1:55 PM
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DOCHAGERTY
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NOX failures can be due to carbon build up in the combustion chambers. I would need to know all the gas percentages and parts per million to plug into an equation and try and determine if the cat is at fault or if there is something in the engine or perhaps the injection system that is the cause of the failure.
Oct 20, 2011 at 2:22 PM
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