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These codes need attention or not?

  • Thread starter Thread starter CRASH7772
  • Start date Start date Oct 4, 2005

CRASH7772

Member
Apr 27, 2003
401
1
16
NH
Oct 4, 2005
#1
  • Oct 4, 2005
  • #1
This is a 87GT without cruise and swapped to mass air. Also AC and smog are gone but EGR is still in.

KOEO 67,82,85,95 Current
KOEO 29,66,95 Continuous

(these are from Mustang works)
29 (c): VSS (Vehicle Speed Sensor) voltage too low(don't have one)
66 (rc*): MAF (2.3 Turbo, VAF) below minimum test voltage(I unplugged the meter while running the car today and didn't clear it yet)
67 (o): Clutch switch open, AC left on, transmission in gear(In neutral but AC is gone)
82: TAB or AM-1 (Thermactor Air Bypass)/ Secondary Air Injection Diverter (AIRD) solenoid circuit failure, or SCVAC (Speed Control Vacuum) circuit failure (IVSC test)(not sure if this is a issue or not from smog delete)
85 (o): CANP (Canister Purge) solenoid circuit failure(not sure if this is a issue or not from smog delete)
95 (oc): Fuel Pump Monitor circuit problems, processor to pump motor ground. Suspect inertia switch, FP relay, harness(from mass air swap and I assume it isn't needed)



I'm trying to get everything ready before chip burning process at the local dyno shop. I plan on doing a KOER test soon as well.


So any input on trying to do anything with these other than resetting it to clear the one I caused? I'm also aware that the chip will get rid of some of these as well.
 

jrichker

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#2
  • Oct 4, 2005
  • #2
CRASH7772 said:
This is a 87GT without cruise and swapped to mass air. Also AC and smog are gone but EGR is still in.

KOEO 67,82,85,95 Current
KOEO 29,66,95 Continuous
Click to expand...
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.

Code 95 - the 95 code is because at one time or another the fuel pump relay hiccupped and didn't provide power the pump when the computer told it to run. Sometimes this is a one time thing, other times it is a no run or runs poorly condition.

To help troubleshoot the 95 code, follow this link for a wiring diagram http://www.autozone.com/images/cds/gif/large/0900823d80167162.gif

Using the diagram, check the red/black wire from the fuel pump relay: you should see 12 volts or so. If not, check the inertia switch: on a hatch it is on the drivers side by the taillight. Look for a black rubber plug that pops out: if you don't find it, then loosen up the plastic trim. Check for voltage on both sides of the switch. If there is voltage on both sides, then check the Pink/black wire on the fuel pump relay: it is the power feed to the fuel pump. No voltage there, check the Orange/lt blue wire, it is the power feed to the fuel pump relay & has a fuse link in it. Good voltage there & at the Pink/black wire, swap the relay.

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. If you did a Mass Air conversion, this is probably something you may have skipped hooking up.

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 66 MAF below minimum test voltage.
Insufficient or no voltage from MAF. Dirty MAF element, bad MAF, bad MAF wiring, missing power to MAF. Check for missing +12 volts on this circuit. Check the two links for a wiring diagram to help you find the red wire for computer power relay switched +12 volts. Check for 12 volts between the red and black wires on the MAF heater (usually pins A & B). while the connector is plugged into the MAF. This may require the use of a couple of safety pins to probe the MAF connector from the back side of it.

There are three parts in a MAF: the heater, the sensor element and the amplifier. The heater heats the MAF sensor element causing the resistance to increase. The amplifier buffers the MAF output signal and has a resistor that is laser trimmed to provide an output range compatible with the computer's load tables.

The MAF element is secured by 2 screws & has 1 wiring connector. To clean the element, remove it from the MAF housing and spray it down with electronic parts cleaner or non-inflammable brake parts cleaner (same stuff in a bigger can and cheaper too).

The MAF output varies with RPM which causes the airflow to increase or decease. The increase of air across the MAF sensor element causes it to cool, allowing more voltage to pass and telling the computer to increase the fuel flow. A decrease in airflow causes the MAF sensor element to get warmer, decreasing the voltage and reducing the fuel flow. Measure the MAF output at pins C & D on the MAF connector (dark blue/orange and tan/light blue) or at pins 50 & 9 on the computer.

At idle = approximately .6 volt
20 MPH = approximately 1.10 volt
40 MPH = approximately 1.70 volt
60 MPH = approximately 2.10 volt

Check the resistance of the MAF signal wiring. Pin D on the MAF and pin 50 on the computer (dark blue/orange wire) should be less than 2 ohms. Pin C on the MAF and pin 9 on the computer (tan/light blue wire) should be less than 2 ohms.

There should be a minimum of 10K ohms between either pin C or D on the MAF and ground.

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

http://www.autozone.com/servlet/UiB..._us/0900823d/80/19/59/5a/0900823d8019595a.jsp
 

CRASH7772

Member
Apr 27, 2003
401
1
16
NH
Oct 4, 2005
#3
  • Oct 4, 2005
  • #3
I know why the code 66 popped up (I unplugged the sensor today while the car was running) but I will run the test anyways.

The code 95 and 29 are from the conversion but I don't have a VSS sensor on my car and the 95 doesn't hurt anything from what I have been told (I could have been miss informed) but should be able to be cleared with the chip.

And the other codes are from AC delete and Smog delete but would they be a issue or can they just be cleared with the burnt chip?
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
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59
windsor, Canada
Oct 4, 2005
#4
  • Oct 4, 2005
  • #4
95 and 29 are non issue..I have them as well after conversion and are ignored without any issues.
 
8

87GT 306

New Member
Oct 11, 2004
260
0
0
Springfield MA
Oct 4, 2005
#5
  • Oct 4, 2005
  • #5
I have a code 95 too. I was confused to what it was because we looked in one of the manuals and it wasnt even listed. The only other codes that were thrown were smog related. Now I guess I can rest tonite. I have no smog and have converted to M/A so the 95 doesnt matter?
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
Oct 4, 2005
#6
  • Oct 4, 2005
  • #6
Give this a good read.
http://www.corral.net/tech/powerplant/maf_tech_2.html
 
8

87GT 306

New Member
Oct 11, 2004
260
0
0
Springfield MA
Oct 4, 2005
#7
  • Oct 4, 2005
  • #7
wow thanks for the link that just answered about 5 questions I had.
 
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