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failed emmissions... why?

  • Thread starter Thread starter red-
  • Start date Start date Jun 30, 2004
R

red-

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Sep 12, 2003
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wilbraham, ma
Jun 30, 2004
#1
  • Jun 30, 2004
  • #1
well, here in the great state of MA we have to put up with emmissions testing, and today i got a red racing sticker because i failed the test. i was .29 over the 2.00 limit for HC's, and i'm looking to find out possible reasons/things to check. i don't really have the funds to take to a shop, so any help anybody can give is GREATLY appreciated. i've got 59 days
 

jrichker

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#2
  • Jun 30, 2004
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First step is to dump the codes and see what the computer says is wrong…

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.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

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

Repost the results of your code dump and you can get some help fixing them. That will go a long ways in helping you pass the smog test.
 
R

red-

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#3
  • Jun 30, 2004
  • #3
i was actually gonna head over to autozone to pick up some new wiper blades too, i can just have them dump the codes while i'm there. i'll post an update tomorrow, but thanks thus far jrichker.
 

88stangmangt

Active Member
Nov 25, 2003
2,332
1
48
Stafford,VA
Jun 30, 2004
#4
  • Jun 30, 2004
  • #4
put them cats back on..............LOL could be aloe of things prob just a burnt up cat or bad 02 sensors if that is the case now would be the best time to get that high flow catted bassani H-pipe.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jul 1, 2004
#5
  • Jul 1, 2004
  • #5
a car in good tune should pass the sniffer w/o cats. you dont have an adjustable FPR, right? i was not sure if your sig was literal. you are just runnin rich.

check the lambdas, as 88 stangman mentioned, as well as the ECT and ACT (they can be out of calibration, but not out of spec - no code tossed). i dont have MA, but i bet it could not hurt to clean it. be careful when doin so.

good luck.
 
J

james87gt

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Feb 8, 2003
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Jul 1, 2004
#6
  • Jul 1, 2004
  • #6
post the rest of your numbers but high hc tells you you got a misfire it could be do to fuel or ignition try a good tune up or post the test results and i could point you in the right direction
 

cdog301

Founding Member
Aug 30, 2000
236
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richmond ,ca
Jul 1, 2004
#7
  • Jul 1, 2004
  • #7
emmision fail

I agree with the other guys and here is my two cents: Make sure your car is tuned up( new plugs new cap and rotor timing set to fac specs, oil changed) after all that check out the fuel additive aisle @ autozone for some guarantee pass for emmision testing might help a little can't hurt always makes my coupe blow waaaaaaaaaaaaay clean @ smog time in California!
good luck
 
R

red-

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wilbraham, ma
Jul 1, 2004
#8
  • Jul 1, 2004
  • #8
alright guys, i just got home from autozone. code 81 was the only one that came up, but none of the guys down there knows what that really means. now what?
 

jrichker

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  • Jul 1, 2004
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Code 81 is the code for the Air injection system (smog pump). One or more of the solenoid valves isn't working. The lack of air supplied to the catalyic converters will result in high HC emissions.

See the test path for code 44 & 94 to help troubleshoot the problem.

Codes 94 & 44 - AIR system inoperative - Air Injection
Check vacuum lines for leaks, & cracks. Disconnect the big hose from smog pump: with the engine running you should feel air output. Reconnect the smog pump hose & apply vacuum to the first vacuum controlled valve: Its purpose is to either dump the pump's output to the atmosphere or pass it to the next valve. The next vacuum controlled valve directs the air to either the cylinder heads when the engine is cold or to the catalytic converter when the engine is warm. Disconnect the big hoses from the back side of the vacuum controlled valve and start the engine. Apply vacuum to the valve and see if the airflow changes from one hose to the next.

The two electrical controlled vacuum valves mounted on the rear of the passenger side wheelwell turn the vacuum on & off under computer control. Check to see that both valves have +12 volts on the red wire. Then ground the white/red wire and the first solenoid should open and pass vacuum. Do the same thing to the light green/black wire on the second solenoid and it should open and pass vacuum.

Remember that the computer does not source any power to actuators, relays or injectors, but provides the ground necessary to complete the circuit. That means one side of the circuit will always be hot, and the other side will go to ground or below 1 volt as the computer switches on that circuit.

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)

http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif
 

88stangmangt

Active Member
Nov 25, 2003
2,332
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48
Stafford,VA
Jul 1, 2004
#10
  • Jul 1, 2004
  • #10
man ^^^is a living mustang trouble shooter book.
 
R

red-

New Member
Sep 12, 2003
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wilbraham, ma
Jul 2, 2004
#11
  • Jul 2, 2004
  • #11
ok, i think i may have found the culprit. looking at this pic, if you'll note the white hose and the black hose essentially next to it are broken and duct taped. that could certainly be my problem correct? if so, whereabouts can i find a new set? thanks in advance guys, you've saved me so much $ since i got my car it's not even funny.
 

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jrichker

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  • Jul 2, 2004
  • #12
red- said:
ok, i think i may have found the culprit. looking at this pic, if you'll note the white hose and the black hose essentially next to it are broken and duct taped. that could certainly be my problem correct? if so, whereabouts can i find a new set? thanks in advance guys, you've saved me so much $ since i got my car it's not even funny.
Click to expand...

The white hose goes to the EGR valve.

The black hose is probably the one that feeds the Smog pump control solenoid valves. Tthat would explain the code 81. No vacuum to the solenoid valves means no air from the smog pump to go to the cats or heads. The excess air helps burn up the unburned Hydrocarbons & lowers the HC numbers for the smog test.

I just use ordinary vacuum hose from the auto parts store. I always try to leave a stub piece of the orginal hose at each end to help identify the color and connection for the hose.
 
R

red-

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Sep 12, 2003
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wilbraham, ma
Jul 17, 2004
#13
  • Jul 17, 2004
  • #13
well guys... i patched up the two broken vacuum hoses with some new hose from autozone. disconnected the battery cables for a few mins and hooked them back up (to reset the computer), and have been driving around for the past couple days here and there. went back to autozone to have the codes pulled again, and to my dismay, code 81 came up again. i threw a couple bottles of dry gas in the tank, so i'm not all too worried about the sniffer however, i'd like to see my baby running the way it should. my question is, what other things should i check? thanks in advance again, as i am eternally indebted to this board for all the help i've recieved over the past year or so.
 

jrichker

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#14
  • Jul 17, 2004
  • #14
Go back to my earlier post. See the test path for code 44 & 94 to help troubleshoot the problem.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jul 17, 2004
#15
  • Jul 17, 2004
  • #15
JR will know much better than i, but disconnecting the battery for 'a few minutes' may not have been enough. i would disconnect it, turn on the headlights (to discharge any residual juice in the circuitry in the KAM) and leave it for 30 mins to be sure.
im sure JR will have better ideas on this, but that is the route i would go. you may be seeing your 'old code'.
good luck.
 
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