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Need to shave 20 ppm more from hydrocarbon emissions; Failed Virginia emissions test
Topic Started: Sep 25 2013, 07:41 PM (6,504 Views)
BillHoo
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Woodie
Sep 26 2013, 06:15 AM
BillHoo
Sep 25 2013, 07:41 PM
Dry compression test done in June 2011 wa 100-135-140

Spark plugs showed signs of oil fouling.
Yeah, I guess they did! That's just stone worn out, done, kaput.

I answered this elsewhere, but now this is new information. Your unburned hydrocarbons are oil getting past the rings and unburned fuel because there's no compression. High test usually has more cleaning detergents in it, so it's not a bad idea to try to clean some crap out of a car which has been sitting. Problem is, it's exactly the WRONG thing for passing an emissions test. So is RETARDING the timing, you need more advance to battle unburned hydrocarbons.


In my intitial thoughts on timing I agree with you that advancing should do the trick.

However, I find more information out there indicating that retarding the timing is done to reduce emissions and advancing the timing is to increase fuel efficiency.

Why Retarding Spark Advance Reduces HC Emissions
"we think that the less than MBT spark advance leaves more heat in the combustion chamber(we all know are engines run hotter with retarded spark, more heat rejected into the coolant jackets)."

http://www.nastyz28.com/forum/showthread.php?t=228953

It appears that factory settings are to keep the car within emissions stadards and not to give the automobile owner better fuel efficiency.

I may not mess with the timing at all since I'm only looking at reducing by 20 ppm.

I think that is achievable by using REGULAR gas and cleaning out the EGR.
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The summary of good suggestions that will might get you passed the HC test if you're lucky.

Post #2

Big Rhino
Sep 25 2013, 07:50 PM
Slide the inspector a 20 spot.
:shake
Big Rhino
Sep 25 2013, 07:50 PM
A slight adjustment on the timing and it passed.
Of course. :deal
Big Rhino
Sep 25 2013, 07:50 PM
Rebuild your engine.
^o) Not going to happen, right?

Post #3

David95237
Sep 25 2013, 08:10 PM
I have used a gallon of E85 to pas a test by couple of points
Absolutely. 2 carbons per molecule versus hundreds. Your engine will run on 50% Ethanol. Been there, done that. ^o)

Post #4

Geo Glenn
Sep 25 2013, 08:38 PM


Post #5

truckjohn
Sep 25 2013, 09:54 PM
So... It was running a hair rich at idle....

Amongst other things.... High octane fuel will do that... especially on a standard fuel car set up to run "Standard" factory parameters....

You are putting in a fuel that has more energy per unit... and adding the same amount of air as with the cheaper, lower energy fuel..... then it burns rich...

Then.. Idled around for a *LONG* time so the engine could load up good...

Hmmm....
You don't have to drive around to get the premium fuel out. You can attach a 1/4" hose to the return nipple on the throttle body and run it into a couple of containers. Either do this while the engine is running, or use a jumper wire on the FI relay.

Post #14

gbreadman
Sep 26 2013, 12:41 PM
Replacing the oxygen sensor did it for me. Dropped HC's and CO's like a rock. It was a long time ago, the paperwork is somewhere back there in the garage. Did nothing for the NOx but that was expected. Does the 89 have an o2 sensor??


What causes high hydrocarbon?

1. Improper ignition timing.
2. Defective ignition components.
3. Lean fuel mixture.
4. Defective catalytic converter
5. Defective air injection components.
6. Low cylinder compression.

Overhaul the engine and install a new catalytic converter, and you'll sail through like a champ.

Pick the cheap and easy fixes and hope it works. :news
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2000Firefly1.3L
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vr4
Sep 26 2013, 11:41 AM
It's simple. The burning oil is killing your readings. Fix that. No real other way to magically clean things up.
he should just drain the oil and run through the smog test without any oil. that way the oil won't burn past the rings.
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v8440
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High HC is normally rich, unless it's so lean it's misfiring, right? If so, use just one of the sensor fooling tricks in the thread here about such things. I think it's in the performance and mileage forum. A $1 resistor literally might make your car pass the HC test with flying colors.
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v8440
Sep 26 2013, 08:27 PM
High HC is normally rich, unless it's so lean it's misfiring, right? If so, use just one of the sensor fooling tricks in the thread here about such things. I think it's in the performance and mileage forum. A $1 resistor literally might make your car pass the HC test with flying colors.
Right. A 172 ohm resistor inserted in the inlet air sensor connector would lean out the mixture a bit.

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Memphis metro


2000Firefly1.3L
Sep 26 2013, 08:06 PM
vr4
Sep 26 2013, 11:41 AM
It's simple. The burning oil is killing your readings. Fix that. No real other way to magically clean things up.
he should just drain the oil and run through the smog test without any oil. that way the oil won't burn past the rings.
I used to work with a bunch of guys who drove ol wore out cars that smoked. The inspection station would not even inspect a car that smoked. They went in together and bought a case of this http://www.smokelessoil.com/ . Come inspection time, they would drain their oil and fill their engine with this. Go to inspection, come home and drain it back out and bottle it up and put their oil back in till the next guy needed inspection.
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00Metro
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Register it in a different city/state. Thank goodness VA hasn't instilled that emissions crap on us down here in Hampton Roads.
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Woodie
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BillHoo
Sep 26 2013, 06:59 PM
However, I find more information out there indicating that retarding the timing is done to reduce emissions and advancing the timing is to increase fuel efficiency.
It's far more complicated than that, there are multiple different things they are testing for and what increases one decreases the others. On Metros, the factory recommended (way retarded) timing was done to reduce Oxides of Nitrogen (NOx). With your very low compression, you're never going to have a problem with that. Advancing the timing makes the engine burn the fuel more completely, increasing power and mileage and decreasing the amount of Unburned Hydrocarbons in the exhaust. This is what you need.

I think you're going to find, very soon, that when it gets cold out you're not going to be able to get it started at all.


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High MX
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We could be over-thinking this a bit. Looking at your test results I noticed it only failed at low speed/idle. You only failed by 20ppm which leads me to believe that the car loaded up sitting there idling. The rest of the results look fine. If it were me, I would run the gas you have in there out and fill up with regular unleaded then go retest. While you are running the tank out, stop by and talk to the inspectors when they aren't busy to see if they have any pointers. Ask them if you get better test results in the morning with cool temps and lower humidity or in the afternoon with higher temps and humidity. See if they recommend any particular brand of gas that gives better test results. It won't hurt to go back and retest. If anything, it will validate the test results.
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BillHoo
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I've run about 220 miles on the tank of Premium on the freeway with some fuel injector cleaner. I think that's enough "cleaning". I can siphon off the rest and fill with regular now.

I checked the vaccuum hoses this morning and found one that was really loose. I cut the appropriate length and replaced it.

Does anyone know if the 89 Metro has an EGR valve? I cannot seem to find it. In my 93 it's just to the right of the PCV valve.

I'm expecting to see the EGR here:
Posted Image

Instead, I'm seeing this:
Posted Image

I forget my high school chemistry, but at 20 parts per million, I'm wondering if I should use that equation with Avagadro's number to convert moles to grams and figure out how much hydrocarbon I need to displace in order to achieve that miniscule 20 PARTS PER MILLION. What is that? less than a gram of hydrocarbon?

Just replacing the Premium gas with regular and maybe adding a bottle of gas line dryer, like HEET should do it.
Edited by BillHoo, Sep 27 2013, 08:46 AM.
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Memphis metro


Not to be a killjoy but after doing all that I bet your next inspection will give higher numbers. :shit
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BillHoo
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I just hooked up the ignition jumper and used my timing light.

it's set at about 17 or 18 degrees.

----- V
20 . . . . . 10 . . . . . 0
Edited by BillHoo, Sep 27 2013, 09:27 AM.
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BillHoo
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BillHoo
Sep 27 2013, 07:32 AM
I've run about 220 miles on the tank of Premium on the freeway with some fuel injector cleaner. I think that's enough "cleaning". I can siphon off the rest and fill with regular now.

I checked the vaccuum hoses this morning and found one that was really loose. I cut the appropriate length and replaced it.

Does anyone know if the 89 Metro has an EGR valve? I cannot seem to find it. In my 93 it's just to the right of the PCV valve.

I'm expecting to see the EGR here:
Posted Image

Instead, I'm seeing this:
Posted Image

I forget my high school chemistry, but at 20 parts per million, I'm wondering if I should use that equation with Avagadro's number to convert moles to grams and figure out how much hydrocarbon I need to displace in order to achieve that miniscule 20 PARTS PER MILLION. What is that? less than a gram of hydrocarbon?

Just replacing the Premium gas with regular and maybe adding a bottle of gas line dryer, like HEET should do it.
Yea, with my luck.
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BillHoo
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Woodie
Sep 27 2013, 06:01 AM
BillHoo
Sep 26 2013, 06:59 PM
However, I find more information out there indicating that retarding the timing is done to reduce emissions and advancing the timing is to increase fuel efficiency.
It's far more complicated than that, there are multiple different things they are testing for and what increases one decreases the others. On Metros, the factory recommended (way retarded) timing was done to reduce Oxides of Nitrogen (NOx). With your very low compression, you're never going to have a problem with that. Advancing the timing makes the engine burn the fuel more completely, increasing power and mileage and decreasing the amount of Unburned Hydrocarbons in the exhaust. This is what you need.

I think you're going to find, very soon, that when it gets cold out you're not going to be able to get it started at all.


Just took a look at the timing. Looks like it's set at abouy 17.

Can it go any more?
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There is no EGR valve on a 1989.

You're supposed to block the vacuum lines to the distributor when setting the ignition timing.

You do not need to jumper the wires on the connector. This procedure is for cars with electronic advance distributors.

Refer to the sticker on the bottom of the hood for timing specifications and procedures.

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