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Help with failed emissions (maryland)

  • Thread starter Thread starter bills93notch
  • Start date Start date May 22, 2007

bills93notch

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Feb 1, 2007
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May 22, 2007
#1
  • May 22, 2007
  • #1
I took the car in for an emissions test and as predicted it failed!

all emissions equip is on the car cats etc ....

here are the numbers

HC- limit 0001.0000 actual 0003.7348

NOX limit 0002.2000 actual 0003.5650

they said it was unburned fuel and high temps in the combustion chamber

any imput would be appreciated!
 

jrichker

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#2
  • May 22, 2007
  • #2
High NO - high combustion temps - retard timing, check EGR for operation.
High CO - EGR isn't working - fix it.
High HC - fuel mixture too rich - check O2 sensors, smog pump, and cats. Clean MAF element. Do the ethanol thing as suggested.

How to pass emissions testing:

1.) Make sure all the emissions gear the car was made with is present and connected up properly. That includes a working smog pump and cats.

2.) Make sure that you have fresh tune up with spark plugs, plug wires, cap, rotor, fuel & air filters. An oil & filter change is a good idea while you are at it.

3.) Dump the codes and see what the computer says is wrong…Codes may be present in the computer even if the Check Engine light isn’t on.

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.
See http://www.troublecodes.net/Ford/
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html





IF your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.

Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.

Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is less than $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see http://www.midwayautosupply.com/p-7208-equus-digital-ford-code-reader-3145.aspx– It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30.


4.) Post the codes and get help to fix them. Don’t try to pass with codes not fixed. Clearing the computer just temporarily removes them from memory, it doesn’t fix the problem that caused the code to be set.

5.) Be sure to do the testing on a hot engine. Drive for 15-20 minutes prior to taking the test to get operating temps up into the normal range. Do not shut off the engine while waiting for your turn on the test machine. An engine up to full operating temperature puts out fewer emissions.
 

cjones

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Jul 20, 2002
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May 22, 2007
#3
  • May 22, 2007
  • #3
make sure your timing is 8-10* over advanced timing could cause those results.
 

cjones

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May 22, 2007
#4
  • May 22, 2007
  • #4
jrichker said:
High NO - high combustion temps - retard timing, check EGR for operation.
High CO - EGR isn't working - fix it.
High HC - fuel mixture too rich - check O2 sensors, smog pump, and cats. Clean MAF element. Do the ethanol thing as suggested.
Click to expand...

Jrichker,
i don't want to be a pain cause you give great help to people here but the emission data above doesn't seem right.

High NOx = correct
High CO = Rich condition
High HC = Lean condition and or missfire, timing, and in some cases extreme rich condition

the EGR is designed to help control combustion temps
 

jrichker

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In Remembrance. Thank you for your contributions
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Dublin GA
May 22, 2007
#5
  • May 22, 2007
  • #5
cjones said:
Jrichker,
i don't want to be a pain cause you give great help to people here but the emission data above doesn't seem right.

High NOx = correct
High CO = Rich condition
High HC = Lean condition and or missfire, timing, and in some cases extreme rich condition

the EGR is designed to help control combustion temps
Click to expand...

After doing some Google research, I have validated your input. I will revise the test path to include your information.
 
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