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Mustang Computer Codes.

  • Thread starter Thread starter my89stangGT
  • Start date Start date Sep 15, 2009
M

my89stangGT

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May 23, 2003
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Oklahoma
Sep 15, 2009
#1
  • Sep 15, 2009
  • #1
I ran a code check on my 1989 mustang GT and I pulled codes 81, 82, 85. What are these codes? I looked in the manual but I dont not understand what sensors they are talking about.
 

liljoe07

5 Year Member
Feb 18, 2009
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Cartersville,Ga
Sep 15, 2009
#2
  • Sep 15, 2009
  • #2
81 - Secondary Air Diverter Circuit Failure (O)
82 - Secondary Air Bypass Circuit Failure (O)

85 - CANP Circuit Failure (O)

Sounds like the for the top 2 are the TAB and TAD solenoids are not hooked up.

Are You running the SMOG system?

For 85, thats the canister purge solenoid. Are you still using it?
 

jrichker

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Sep 15, 2009
#3
  • Sep 15, 2009
  • #3
Code 81 – Secondary Air Injection Diverter Solenoid failure AM2. The solenoid valve located on the back side of the passenger side wheel well is not functional. Possible bad wiring, bad connections, missing or defective solenoid valve. Check the solenoid valve for +12 volts at the Red wire and look for the Lt Green/Black wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the LT Green/Black wire for the solenoid valve.

With the with the ignition on, look for 12 volts on the red wire on the solenoid connector. No 12 volts and you have wiring problems.

With the engine running, stick a safety pin in the LT Green/Black wire for the solenoid valve & ground it. That should turn the solenoid on and cause air to flow out the port that goes to the pipe connected to the cats. If it doesn't, the valve is bad. If it does cause the airflow to switch, the computer or wiring going to the computer is not signaling the solenoid valve to open.

Putting the computer into self test mode will cause the solenoid valve to toggle. If you listen carefully, you may hear it change states.

If you have catalytic converters, you need to fix this code. If not you can use a TAB and TAD eliminator.

Code 82 – Secondary Air Injection Diverter Solenoid failure AM1. Possible bad wiring, bad connections, missing or defective solenoid 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

With the engine running, stick a safety pin in the Red/White wire for the solenoid valve & ground it. That should turn the solenoid on and cause air to flow out the port that goes to the pipe connected to the heads. If it doesn't, the valve is bad. If it does cause the airflow to switch, the computer or wiring going to the computer is not signaling the solenoid valve to open.

If you have catalytic converters, you need to fix this code. If not you can use a TAB and TAD eliminator.

Both 81 & 82 codes usually mean that some uneducated person removed the solenoid control valves for the Thermactor Air system in an attempt to make the car faster. It doesn't work that way: no working control valves can cause the cat converters to choke and clog.


Code 85 - CANP solenoid - The Carbon Canister solenoid is inoperative or missing. 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.

Charcoal canister plumbing - one 3/8" tube from the bottom of the upper manifold to the rubber hose. Rubber hose connects to one side of the canister solenoid valve. Other side of the solenoid valve connects to one side of the canister. The other side of the canister connects to a rubber hose that connects to a line that goes all the way back to the gas tank. There is an electrical connector coming from the passenger side injector harness near #1 injector that plugs into the canister solenoid valve. It's purpose is to vent the gas tank. The solenoid valve opens at cruse to provide some extra fuel. The canister is normally mounted on the passenger side frame rail near the smog pump pulley.



It does not weigh but a pound or so and helps richen up the cruse mixture. It draws no HP & keeps the car from smelling like gasoline in a closed garage. So with all these good things and no bad ones, why not hook it up & use it?


The purge valve solenoid connector is a dangling wire that is near the ECT sensor and oil filler on the passenger side rocker cover. The actual solenoid valve is down next to the carbon canister. There is about 12"-16" of wire that runs parallel to the canister vent hose that comes off the bottom side of the upper intake manifold. That hose connects one port of the solenoid valve; the other port connects to the carbon canister.
Purge valve solenoid:



The carbon canister is normally mounted on the passenger side frame rail near the smog pump pulley.
Carbon Canister:
 
M

my89stangGT

New Member
May 23, 2003
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Oklahoma
Sep 16, 2009
#4
  • Sep 16, 2009
  • #4
Thanks for the help. The smog stuff is off except for the canister because like you said there is a gas smell so I left the canister hooked up.
 

liljoe07

5 Year Member
Feb 18, 2009
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Cartersville,Ga
Sep 16, 2009
#5
  • Sep 16, 2009
  • #5
Posted via Mobile Device

SMOG off, then don't worry about 81 and 82.
 
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