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aaRGH when will the error codes stop (CODE 67)

  • Thread starter Thread starter webshot
  • Start date Start date Jul 8, 2007
W

webshot

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Jul 8, 2007
#1
  • Jul 8, 2007
  • #1
I just got out of the woods on the egr error codes (thx stangnet). Now I am getting a 67 error code. But it seems to pop up when I use my air conditioning? But I have read here that code 67 is having to do with neutral safety switches and such. I also read to pull codes while car is in neutral to get rid of this.

Any advice?

Also a guy was telling me that I should pull my codes with the engine running as well. I did my test with the jumper wire and jey in the on position. Should I do the same with the engine running?

btw
same car 88 mustang, no mods besides flow master mufflers. Cali car with all smog stuff running. and it is a 5 speed w/AC.
 

HISSIN50

"How long does it take to get help in here?
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#2
  • Jul 8, 2007
  • #2
Some stangs dont like to spit KOER codes with a 67 stored. As you noted, ensure the car is in neutral and that the AC is off.

Good luck.
 

jrichker

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#3
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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.

The computer wants to make sure the A/C is off due to the added load on the engine for the engine running tests. It also checks to see that the transmission is in Neutral and the clutch depressed (T5, T56, Tremec 3550 & TKO)). This prevents the car from being driven while the computer is in test mode. Key On Engine Running test mode takes the throttle control away from the driver for several tests. This could prove hazardous if the computer was jumpered into test mode and then driven.

The NSS code 67 can be bypassed for testing. You will need to temporarily ground computer pin 30 to the chassis.
 
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#4
  • Jul 8, 2007
  • #4
KOER = Key On Engine Running? Just to make sure. Because all the codes and stuff I have gotten was without the engine running. Just Key On. Also how does one ground the computer? Do you have a diagram for that jrichker?

Also one more question, if the engine is to be running when I do the jumper (paper clip) test. Do I connect the paper clip then start the car or connect paper clip after car is started. Sorry for the silly questions just want to make sure I do things right
 

jrichker

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The next part you need to buy is a Chiton's Service Manual for your car. It will have all the details on the tests and how to run them.

Jumper the test connector to dump the codes and then start the car. The CEL will flash 11 and then 4, then the computer will test the EGR and IAC/IAB. After that it will dump the engine running codes.

The best thing to do make sure the A/C is off, the transmission is in Neutral and the clutch pedal is pressed to the floor. That should cure the 67 code unless you have faulty wiring or a bad switch.

I recommend that you correct any problems with the code 67 rather than jumpering the computer pin 30 to ground.

AutoZone wiring diagrams

http://www.autozone.com/servlet/UiB..._us/0900823d/80/16/71/3c/0900823d8016713c.jsp for 79-88 model Mustangs

http://www.autozone.com/servlet/UiB..._us/0900823d/80/19/59/5a/0900823d8019595a.jsp for 89-93 model Mustangs

http://www.autozone.com/servlet/UiB..._us/0900823d/80/1d/db/3c/0900823d801ddb3c.jsp for 94-98 model Mustangs

Computer pin 30 uses a Lt blue/yellow wire. Remove the passenger side kick panel and then remove the plastic cover from the computer wiring connector. Use a safety pin to probe the connector from the rear. Jumper the safety pin to the ground near the computer.
Be sure to remove the jumper BEFORE attempting to drive the car!!!
 
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#6
  • Jul 8, 2007
  • #6
Ok did your test and it now I get a 11 code which seems to be good. I have a Haynes manual but I didnt find a section on codes. Seems I need to get a chiltons.

Thanks man
 
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#7
  • Jul 8, 2007
  • #7
EDIT change that.....with the engine on and doing the test with clutch all the way to the floor I got the follow ing code

12, 21, 94, 44 (in that order)....they all seem to be somehow air related so say troublecodes.net
 
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#8
  • Jul 8, 2007
  • #8
oh and a lil more info, I replced my smog pump about 400 miles ago. Is the car driveable with the above error codes? Also as far as error code 21 goes, I notive my overflow bottle is not working and seems to have a place for a sensor. I bought the car like this and there was no cap. Would this cause the error 21? Can someone take a picture of their stock radiator setup?
 

HISSIN50

"How long does it take to get help in here?
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#9
  • Jul 8, 2007
  • #9
webshot said:
Would this cause the error 21?
Click to expand...

The computer has no idea if the reservoir sensor is present. That code is for the ECT, which tells the computer your engine temps. It is fairly important and is most felt when starting the car or when the car is very cold or hot. Jrichker will be along with a tech note about it.

Good luck.
 
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#10
  • Jul 8, 2007
  • #10
thanks for the info. ANd I really appreciate the help to this point. I've learned a bunch from this post alone and saved a few bucks in the process. A local shop wanted 90 bucks to do what I did with the paper clip. My main concern at this point is if it safe to drive. The code 12 low idle I think I fixed by raising the idle at the TB
 

jrichker

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Code 21 – ECT sensor out of range. Broken or damaged wiring, bad ECT sensor.
Note that that if the outside air temp is below 50 degrees F that the test for the
ECT can be in error.


The ECT sensor has absolutely nothing to do with the temperature gauge. They are
different animals. The ECT sensor is normally located it the RH front of the engine in
the water feed tubes for the heater.

The ACT & ECT have the same thermistor, so the table values are the same

ACT & ECT test data:

Use Pin 46 on the computer for ground for both ECT & ACT to get most accurate
readings.

Pin 7 on the computer - ECT signal in. at 176 degrees F it should be .80 volts

Pin 25 on the computer - ACT signal in. at 50 degrees F it should be 3.5 volts. It is
a good number if the ACT is mounted in the inlet airbox. If it is mounted in the lower
intake manifold, the voltage readings will be lower because of the heat transfer.

Voltages may be measured across the ECT/ACT by probing the connector from
the rear. A pair of safety pins may be helpful in doing this. Use care in doing it
so that you don't damage the wiring or connector.

Here's the table :

50 degrees F = 3.52 v
68 degrees F = 3.02 v
86 degrees F = 2.62 v
104 degrees F = 2.16 v
122 degrees F = 1.72 v
140 degrees F = 1.35 v
158 degrees F = 1.04 v
176 degrees F = .80 v
194 degrees F = .61
212 degrees F = .47 v
230 degrees F = .36 v
248 degrees F = .28 v

Ohms measures at the computer with the computer disconnected, or at the sensor with the sensor disconnected.

50 degrees F = 58.75 K ohms
68 degrees F = 37.30 K ohms
86 degrees F = 27.27 K ohms
104 degrees F = 16.15 K ohms
122 degrees F = 10.97 K ohms
140 degrees F = 7.60 K ohms
158 degrees F = 5.37 K ohms
176 degrees F = 3.84 K ohms
194 degrees F = 2.80 K ohms
212 degrees F = 2.07 K ohms
230 degrees F = 1.55 K ohms
248 degrees F = 1.18 k ohms

Diagram courtesy of Tmoss & Stang&2birds



See the following website for some help from Tmoss (diagram designer) & Stang&2Birds
(website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg
 
W

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#12
  • Jul 8, 2007
  • #12
while I am getting around to these is it safe to drive the car? Again thanks
 

jrichker

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#13
  • Jul 9, 2007
  • #13
There are no problems with driving the car if you are concerned about damaging anything.
You may have some performance/driviablity problems that make the car less pleasant to drive,
but they will not damage anything.
 
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