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SMOG and check engine light

  • Thread starter Thread starter Lash
  • Start date Start date Jul 29, 2006

Lash

New Member
Jul 19, 2006
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Pewaukee, WI
Jul 29, 2006
#1
  • Jul 29, 2006
  • #1
For those of you who have removed your smog systems....how do you get the CE light to go off? I have to go get tested for emissions (no visual here......they may check cats but I have a stock h-pipe) and I just need to get the light off....if they see a CE light they'll fail it instantly.

Thanks in advance.
 

The Shape

Founding Member
Jan 11, 2002
2,224
8
49
East ARKANSAS Delta
Jul 29, 2006
#2
  • Jul 29, 2006
  • #2
Just removing the smog pump and it's componets shouldn't set the light off. What all did you remove???
 

vristang

15 Year Member
Mar 31, 2005
4,933
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Seattle
Jul 29, 2006
#3
  • Jul 29, 2006
  • #3
^^^

What have you removed and what codes come up when you pull codes?
 

jrichker

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Jul 29, 2006
#4
  • Jul 29, 2006
  • #4
When the CEL goes on, you are in limp mode. Limp mode means lower power from the engine. You now have a car with less power than a car with proerply functioning smog equipment.
 

Lash

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Jul 19, 2006
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Pewaukee, WI
Jul 29, 2006
#5
  • Jul 29, 2006
  • #5
jrichker said:
When the CEL goes on, you are in limp mode. Limp mode means lower power from the engine. You now have a car with less power than a car with proerply functioning smog equipment.
Click to expand...

Which explains the previous owner running 14.2 @ 95ish mph!!. Kinda slow for the mods IMO. Even pulled 2.0 60's.


I just bough the car 2 weeks ago and am still trying to figure out whats all going on with this thing...lol. Previous owner removed all the smog stuff. Just got the notice in the mail...gotta have it pass emissions by sept. 8th.


Gonna run up to the local autozone and have them pull the codes for me.

After a further look at things....it appears that he had caped some of the lines comming off of the EGR spacer. I'm gonna say this is where the ligh it coming from.

So for the EGR delete...looks like I gotta have somebdy dig into it with a program and clear it out and make it not trigger the light? Or is there another way?


Sorry guys....this is my first mustang. Still trying to learn about these.

Anybody got any pics of how/where the vac lines are supposed to be routed???
 
F

FordGuy88

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Nov 15, 2004
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Park Ridge, IL
Jul 29, 2006
#6
  • Jul 29, 2006
  • #6
They have egr sims which plugs into the connector that plugs into the egr and it makes it believe that it is working.
 

Lash

New Member
Jul 19, 2006
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Pewaukee, WI
Jul 29, 2006
#7
  • Jul 29, 2006
  • #7
Well...the actual EGR is hooked up (plug and vac line that "t"'s near the firewall. Is there supposed to be VAC lines going into the EGR spaer?


I went and got in scanned. 6 codes total. The A/C has also been removed on ths car. Will the A/C code cause the car to still go into limp mode? I believe the codes came up because somebody probably fliped the swithch to turn on the A/C but it's deleted so it poped a code...right?

KOEO Codes:

31 EGR valve position or exhaust pressure transducer sensor voltage low

67 A/C on during KOEO or nuetral drive switch open or manual lever position sensor out of range or neutral pressure switch closed

82 Air management system 1 or inlet control circuit falure

85 Canister purge circuit failure or transaxle error 3-4/4-3 shift selenoid failure


Memory codes:

29 Insufficient input from the vehicle speed sensor

31 EGR valve postition or exhaust pressure transducer sensor voltage low



Can anybody point me in the right direction to get rid of these and fix the problems? Help would be MUCH appreciated.

While I was there...I also picked up a Chiltons manual
 

Lash

New Member
Jul 19, 2006
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Pewaukee, WI
Jul 29, 2006
#8
  • Jul 29, 2006
  • #8
One more thing....


with no visual inspection (except for cats) here in WI....can I still pass emissions with the EGR delete?
 

jrichker

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#9
  • Jul 29, 2006
  • #9
Code 29 - Vehicle Speed Sensor (VSS) is an electronic sender mounted on the speedo pickup gear on the trans. It works the cruse control for both 5 speed and auto trans cars. The VSS is used to tell the computer to speed up the idle as you slow to a stop. This helps keep the engine from stalling when you slow down for a stop sign or stop light.
Check to see if the electrical connector is plugged into it. Clean the connector & contacts with non flammable brake parts cleaner prior to replacing the sensor, as that may fix the problem. The sensor cost is under $30 and it is easy to replace.

CODE: 31 (KOEO) - EVP circuit below minimum voltage. Vref (5 volt reference voltage supplied by the computer) missing or broken wire or bad connection in circuit. Use a DVM to check for 5 volts on the orange/white wire. If it is missing, look for +5 volts at the orange/white wire on the TPS or MAP sensor located on the firewall near the center of the car. Use the black/white wire for the ground for the DVM.
With the sensor removed from the EGR and still connected, press the plunger and watch the voltage change on the brown/lt green wire. Pull the passenger side kick panel and measure the voltage at the computer. You will need to remove the plastic cover over the wires and probe them from the backside. A safety pin may prove very useful for this task. Use pin 27, EVR input (brown/lt green wire) and pin 46, signal ground (black/white wire) to measure the voltage. The orange/white wire is Vref and should always be 5 volts -/+ .25 volt. Be sure to measure Vref at the EGR sensor to rule out any broken wires or bad connections.


Code 67 - clutch not depressed (5 speed) or car not in neutral or park (auto) or A/C in On position when codes where dumped. Possible neutral safety switch or wiring problem. This code may prevent you from running the Key On Engine On tests. You can generally ignore this code, since it has no effect on engine performance.

Code 82 – Secondary Air Injection Diverter Solenoid failure AM1. The dump valve air diverter valve (front vacuum operated valve) isn’t working on the Thermactor Air System (smog pump). Look for broken or missing vacuum lines on the solenoid valve to the diverter valve Check the solenoid valve for +12 volts at the Red wire and look for the Red/White wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the Red/White wire for the solenoid valve

Code 85 - CANP solenoid - The Carbon Canister solenoid is inoperative. Check vacuum lines for leaks and cracks. Check electrical wiring for loose connections, damaged wiring and insulation. Check solenoid valve operation by grounding the gray/yellow wire to the solenoid and blowing through it.
The computer provides the ground for the solenoid. The red wire to the solenoid is always energized any time the ignition switch is in the run position.
 
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