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PULLED CODES!! HELP

  • Thread starter Thread starter ninety15.0
  • Start date Start date Apr 5, 2004

ninety15.0

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Mar 10, 2004
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Apr 5, 2004
#1
  • Apr 5, 2004
  • #1
Ok so i pulled codes today, and i got a ton of them stored in the computer but i dont have a CE light. The car would bog like crazy at like 2.5 or 3k rpm, and wouldnt pull hard at all. my mods are in my sig and i just did a real extensive tune up. the codes are- 81-which should be thermactic air diverter solenoid:circuit failure. 87-fuel pump relay circuit failure. 84-EGR vacuum solenoid/vacuum regulator/ or vacuum shut off. 44-problems in thermactic air system. and finally 97-failure of right side 02 sensor. PLEASE HELP me make sense of all these codes and tell me which ones to concentrate on first. The fuel pump is making a lot of noise and i will be removing the smog pump and all the check valves and hoses next weekend. So i need to know what to do with all this stuff.....my poor baby is running like $hit...i feel like im driving a stock civic!!! Thanks in advance!
 

sixty9boss302

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Jun 27, 2001
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Pittsburgh PA or Rochester NY
Apr 5, 2004
#2
  • Apr 5, 2004
  • #2
Maybe the egr valve is stuck open causing the loss of power at high rpm's. This possibly could cause the right O2 sensor to get different readings from the left. I'd try fixing the egr first.
I don't know how the fuel pump problem would be related. If you fix the egr problem and the fuel pump is still louder than normal its probably time to replace it.
 

ninety15.0

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Apr 6, 2004
#3
  • Apr 6, 2004
  • #3
Thanks for the advice, does anyone else have any suggestions. What should i do about my EGR just take the whole thing off?!?! i have no idea how to go about plugging all the vac lines from the egr and all the related $hit. any help with that would be awesome.!!
 

jrichker

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  • Apr 6, 2004
  • #4
Code 81 – Secondary Air Injection Diverter Solenoid failure AM2. The secondary air diverter 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. Look 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.

Code 84 - EGR Vacuum Regulator - Solenoids. The EGR vacuum regulator solenoid is inop, missing vacuum, broken vacuum lines, vacuum leaks, or bad electrical wiring from the computer or no power to the solenoid.

Code 87 – fuel pump primary circuit failure. check inertia switch, wiring to/from inertia switch, red wire going to inertia switch for +12volts. Check other side of inertia switch for +12 volts.

To help troubleshoot the 87 code, follow this link for a wiring diagram http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif


Codes 94 & 44 - 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, 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

Be sure that there are no vacuum leaks/cracked or damaged vacuum hoses. The EGR and Thermator air System (smog pump) systems have usage of vacuum as a common failure point.
 
S

sublime29

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Mar 18, 2004
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Apr 6, 2004
#5
  • Apr 6, 2004
  • #5
You always fix codes in the order given.Usually the 1st codes is the cause of the rest and fixes them all.Once you fix 1st code unplug negative battery terminal for at least 5 minutes and put it back on.That resets the computer then go on to next code reseting computer each time you fix the next one.
 
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