Failing Emissions Test

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Too bad you used seafoam. Fresh plugs may help, now.

The 10% alcohol gas would almost certainly be better for emissions testing readings.
And higher octane should have no bearing. If it is cold, it may even make things worse!

An Italian tune up at his point could help.
See if you can test this elsewhere before you bring it back in for the State test. [Even if you pay!]
You only get so many tries at the State facility!
 
Originally Posted By: mechtech2
Too bad you used seafoam. Fresh plugs may help, now.

The 10% alcohol gas would almost certainly be better for emissions testing readings.
And higher octane should have no bearing. If it is cold, it may even make things worse!

An Italian tune up at his point could help.
See if you can test this elsewhere before you bring it back in for the State test. [Even if you pay!]
You only get so many tries at the State facility!


It was the most beautiful seafoam show ever! Never seen a car smoke that much before. It feels like it clean up a lot of [censored], but without pulling the heads before and after the seafoam job, we'll never know.

Plugs were changed after I got rid of all the seafoam smoke. And I did a few italian tune ups about an hour before I tested it.

Here in BC, there is no limit to the tests. The government loves grabbing your money.
 
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Alright, got home from work, and at operating temperature I initiated an EEC test.

Key on engine off revealed my continous memory code was a 172. The regular KOEO was a 111-pass.

During the run test, it also came up as a 111. I then proceeded to do the cylinder balance test, and came up with a 99=all cylinders equal.

Code 172 is

HEGO sensor circuit indicates system lean (right side)

So looks like it should be my oxygen sensor. If it's wrongfully indicating that it is lean, that means the mixture is richening up, failing my test.
 
i would change the o2 sensor, and then run the tank down low, use denatured alcohol 25% alcohol/ 75% fuel and go test.
 
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Originally Posted By: mechjames
Originally after I bought the car, I took it through the test, and failed on Hydrocarbons only.

The readings are:
HC g/km= 0.7553 MAX 0.5000 FAIL
CO g/km= 2.1388 MAX 9.3200 PASS
NOx g/km= 1.0371 MAX 1.2400 PASS


What does the Hydrocarbons reading mean? Is that unburned gasoline going out the tail pipe?

Have you made any attempt to clean the fuel injectors?

A scan tool might also help you determine if you have faulty injector(s) or you have vacuum leak.
 
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Note that an O2 sensor code may be the actual sensor, OR a lean/rich condition and the O2 is actually doing it's job OK.
Vacuum leaks from any line or it's connection, PCV SYSTEM, intake manifolding or piping, injector seals, and whatever else you see should be perfect.
A bit tedious, but manually/visually check these things as best you can.
 
Originally Posted By: mechtech2
Note that an O2 sensor code may be the actual sensor, OR a lean/rich condition and the O2 is actually doing it's job OK.
Vacuum leaks from any line or it's connection, PCV SYSTEM, intake manifolding or piping, injector seals, and whatever else you see should be perfect.
A bit tedious, but manually/visually check these things as best you can.


I went all over every clamp, hose, and connection today. The rear O2 sensor said Ford on it. It might have just been factory and worn out.

I've changed both sensors, and the exhaust actually smells a bit better (unscientific test, i know.)

The PCV system on this car consists of a hose run from the valve cover to the throttle body. There is no PCV valve on this car. Surprised me too, until I read the service manual.
 
Originally Posted By: spasm3
i would change the o2 sensor, and then run the tank down low, use denatured alcohol 25% alcohol/ 75% fuel and go test.


+1 on the alcohol.

Creating a controlled vacuum leak works miracles for an idle emissions test, too. No, the ecm won't compensate and richen up the mixture THAT quickly and a small to medium sized vacuum leak will be out of the short-term fuel trim parameters anyway.
Fish aquarium valves are great for creating an adjustable vacuum leak. (Don't ask me how I know although my current state doesn't do emissions tests.)
 
Originally Posted By: Scdevon
Originally Posted By: spasm3
i would change the o2 sensor, and then run the tank down low, use denatured alcohol 25% alcohol/ 75% fuel and go test.


+1 on the alcohol.

Creating a controlled vacuum leak works miracles for an idle emissions test, too. No, the ecm won't compensate and richen up the mixture THAT quickly and a small to medium sized vacuum leak will be out of the short-term fuel trim parameters anyway.
Fish aquarium valves are great for creating an adjustable vacuum leak. (Don't ask me how I know although my current state doesn't do emissions tests.)


I don't get tested at idle. They only do a drive test with the newer cars.

So latest test results:

HC g/km = 0.8971 MAX 0.500 FAIL
CO g/km = 3.4085 MAX 9.3200 PASS
NOx g/km = 1.6923 MAX 1.2400 FAIL

At this point I decided to remove the SPOUT jumper, as instructed on a SHO forum. Results got better but not perfect to pass.

HC g/km = 0.6266 MAX 0.5000 FAIL
CO g/km = 3.3641 MAX 9.3200 PASS
NOx g/km = 0.9225 MAX 1.2400 PASS

But not enough. A shop I know is going to test the cat converters, but i'm sure now that is the issue here. New cats should bring my HC down enough to pass emissions.

Also, aftermarket cats usually only last a few years, and they look like they have been changed already.
 
Is there an e 85 station near you? You might try running the tank down really really low then putting say 3 gallons of e-85 in. Go test then fill the tank with regular fuel.
 
Originally Posted By: spasm3
Is there an e 85 station near you? You might try running the tank down really really low then putting say 3 gallons of e-85 in. Go test then fill the tank with regular fuel.


We don't have E85 in canada.
 
Originally Posted By: mechjames
Originally Posted By: spasm3
Is there an e 85 station near you? You might try running the tank down really really low then putting say 3 gallons of e-85 in. Go test then fill the tank with regular fuel.


We don't have E85 in canada.

Run it low on fuel then add denatured alcohol i'd go for at least 25% alcohol to fuel!
 
I looked the catalytic converter up on rockauto for your '94 3.2L SHO.
They list the direct fit Walker, looks like they do 2 converters for the replacement.
It is $374.79 (US).
I put a Walker Direct fit on my '96 3.8L windstar, while not as good as a OEM, it did the job for a number of years.
Walker is a good name in the aftermarket.

Rockauto also has the Motorcraft upstream oxygen sensors for $37.79 or $48.79 (US) each.
You have 2 upstream sensors.
If you get a code showing 1 sensor failing, you could switch the 2 sensors and see if the problem moves, to see if it is a sensor failure or a actual condition being reported by the sensor.
At this age, if I were replacing 1 sensor, I would replace both sensors...Reason, then you have a matched pair.
Oxygen sensors switch slower as they age, and having matched switching speeds will give you a more ballanced condition between the 2 cylinder banks.

If you are not a member of a SHO forum, I would recommend that you find one as this is a good way to be on top of things for your specific vehicle.
I recommend this for any vehicle that one plans to keep.

If you change the catalytic coverter yourself, use extra care with any "flex" pipe.
They recommend you support the flex pipe with a wire....and not let it dangle.
Preventing extra flexing will prevent it from being damaged and causing you yet another part to replace.
 
Originally Posted By: wiswind
I looked the catalytic converter up on rockauto for your '94 3.2L SHO.
They list the direct fit Walker, looks like they do 2 converters for the replacement.
It is $374.79 (US).
I put a Walker Direct fit on my '96 3.8L windstar, while not as good as a OEM, it did the job for a number of years.
Walker is a good name in the aftermarket.



No one around here stocks it for the SHO, so I ordered the walker cats from rockauto on Tuesday. I had the 5% discount code which brought it down to $356.05 and Walker has a mail in rebate for $30, so effectively i'm paying $326.05 + shipping for 2 good converters and new y-pipe. A good deal, because I didn't just want to weld in 2 new universals, and might have had a poor fit because of the converters in the y-pipe in the FWD v6.

Originally Posted By: wiswind

Rockauto also has the Motorcraft upstream oxygen sensors for $37.79 or $48.79 (US) each.
You have 2 upstream sensors.
If you get a code showing 1 sensor failing, you could switch the 2 sensors and see if the problem moves, to see if it is a sensor failure or a actual condition being reported by the sensor.
At this age, if I were replacing 1 sensor, I would replace both sensors...Reason, then you have a matched pair.
Oxygen sensors switch slower as they age, and having matched switching speeds will give you a more ballanced condition between the 2 cylinder banks.

I already replaced the sensors right when I discovered the code as per an above post. They are both new, and matched pair, with OEM exact fit for the car.

Originally Posted By: wiswind

If you are not a member of a SHO forum, I would recommend that you find one as this is a good way to be on top of things for your specific vehicle.
I recommend this for any vehicle that one plans to keep.

I'm on SHOforum and TaurusClub, but here on BITOG replies come quicker, and seem more knowledgeable. For example, I posted on Taurus club about my Low beams not working, but daylamps and highbeams work fine. Fog lights weren't working either. I even changed the lightswitch with a good working one, and still had no power to the low beam pins at the sockets, even after changing the relay and checking the fuse. Someone on TaurusClub said:

"Maybe your low beams are burnt out."

Well, no power to the sockets, How can that be? Plus my Fog lights aren't working either. Looked in the service manual, and saw that there is a headlight dimmer in the multifunction switch, so I changed that and they all worked great again.

Not every forum can hit a good response like BITOG.

Now Explorerforum is great. Allpar is great too. Stratusphere, not so much. They're more into mods then problemsolving.

Originally Posted By: wiswind

If you change the catalytic coverter yourself, use extra care with any "flex" pipe.
They recommend you support the flex pipe with a wire....and not let it dangle.
Preventing extra flexing will prevent it from being damaged and causing you yet another part to replace.

Yup, knew this already. It looks like it's leaking already though. Plans are to install a Dynomax Catback or Borla Catback sometime next year.
 
Alright, passed our Aircare Emissions test with flying colors. Everything went below average.

Lesson learned: Don't buy a car with 5 year old hi-flow cheap catalytic converters and expect them to work.
 
Cheap catalytic converters generally don't work. They start throwing the code in 6 months and likely will fail tail-pipe emission test.
 
Originally Posted By: mechjames
Alright, passed our Aircare Emissions test with flying colors. Everything went below average.


What were the final numbers? (I'm nosey)
 
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