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Cant pass emissions! high HC

  • Thread starter Thread starter indk67k
  • Start date Start date May 20, 2011
I

indk67k

New Member
Jan 3, 2011
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May 20, 2011
#1
  • May 20, 2011
  • #1
hello,
after 3 tries i cannot pass my emissions
i have catted h pipe, smog pump, and all my vacuum lines are hooked up.
its only failing on HC
the first time i ran the HC was at 2.834 (with my timing at 16)
the second time i ran i got it down to 2.344 (with timing set at 10)
third time i ran it shot way up to 3.667 (with timing at 10 and spout pulled)
the HC limits here are 2.000
i searched here before posting and i followed this

"High NO - high combustion temps - retard timing, check EGR for operation.
High CO – Rich condition - fuel pressure too high, check O2 sensors, replace air filter, Clean MAF element.
High HC – Lean misfire, vacuum leak, common misfire due to worn or weak ignition system components. On rare occasions, an overly rich mixture may be the cause. Do the ethanol/E85 fill up as suggested.
High CO & HC - Cat converters, smog pump, and smog pump controls."

im wondering if i would need to set the timing to 6? and im wondering why it shot up with the spout pulled? any ideas or help? thanks!
 

jrichker

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May 20, 2011
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Set the timing at 10 degrees. The Ford engineers have the computer program dialed in for that amount of timing for minumum emissions. Messing with the timing won't do anything to improve your HC readings.

Start looking for the things in the list posted that cause high HC. Dump the computer codes and post your results here. I have a code library tailored for 5.0 Mustangs and you'll get code descriptions and fixes you won't find anywhere else on the Internet.

Dumping the computer diagnostic codes on 86-95 Mustangs

Revised 18-Mar-2011 to advise differences in code information for engine running and engine off codes.

Here's the way 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. You watch the flashing test lamp or Check Engine Light and count the flashes.

Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.

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. You watch the flashing test lamp or Check Engine Light and count the flashes.

See Troublcodes.net Trouble Codes OBD & OBD2 Trouble Codes and Technical info & Tool Store. By BAT Auto Technical





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.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.

89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.



The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.


WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.

What to expect:
You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems. This is crucial: the same wire that provides the ground to dump the codes provides signal ground for the TPS, EGR, ACT and Map/Baro sensors. If it fails, you will have poor performance, economy and driveablity problems

Some 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.

Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.

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

Alternate methods:
For those who are intimidated by all the wires & connections, see Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.

Or for a nicer scanner see Equus - Digital Ford Code Reader (3145) – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30.
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.
 
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