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Code Experts please

  • Thread starter Thread starter 86T-Top
  • Start date Start date Oct 12, 2004

86T-Top

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Jun 29, 2001
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Dublin, PA
Oct 12, 2004
#1
  • Oct 12, 2004
  • #1
I ran the codes on my car today and I think I figured them out, however I would like a second opion on them.

First code 18 C - I have had this code for at least a year and a half. At first I replaced the TFI module but with no luck. Today I unhooked the wiring harness from the TFI module and the computer. I did a continuity test from all the wires that run from the TFI module to the computer, they all gave me 1 ohm except for the dark green / yellow IDM circuit (pin 4), which said it was open. Now I know there is a 22K ohm resistor in this circuit, but where? IS it in the car or in the engine bay? I know that the break is in between the resistor and the computer, because i got a reading of 1 ohm between the TFI connector and the coil connector on this wire.

Am I on the right track with this? Will this give me a drivablity problem, because I have had intermitint performace and gas mileage problems for about a year.

29 C - vehicle speed sensor, I checked for continuity between pins 3 and 6 on the harness and got a reading of 207 ohms. Next I checked the lines individualy and they both read out at 1 ohm each. So I feel that it is the VSS am I correct with this. BTW I used this for a diagram http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif

96 C

Wasn't sure what to do with this so I checked for continuity between pins 37 and 22 on the computer and it gave me 62 ohms. I know that this circuit runs through the coil of a relay so is this reading any good?

This is what the code is
Fuel Pump Circuit Open-Battery To PCM (Others)
So I would assume at one point the fuel pump relay opened up while the car was running and this created an open connection between the battery and pin 22. So I guess that code mean that either there is a loose connection, or either the fuel pump relay, inertia fuel pump switch, or eec power relay is going bad.
Am I right or wrong with this?

Thanks for the help.

Mario
 

86T-Top

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Jun 29, 2001
553
0
17
Dublin, PA
Oct 12, 2004
#2
  • Oct 12, 2004
  • #2
TTT
Anyone have a clue, how about Jrichker you always have an anwser for this stuff.

Thanks,

Mario
 

86T-Top

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553
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Dublin, PA
Oct 13, 2004
#3
  • Oct 13, 2004
  • #3
TTT
 

jrichker

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Oct 13, 2004
#4
  • Oct 13, 2004
  • #4
You are right, there is a 22 K Ohm resistor in the wiring. See http://www.autozone.com/images/cds/gif/large/0900823d80167158.gif
Unfortunately, I don't know where it is.

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. Cost is under $30 and it is easy to replace.

Code 96 – KOEO- Fuel pump monitor circuit shows no power - Power / Fuel Pump Circuits
(Stored Memory code - Service 87 code first if present) Fuel pump relay or battery power feed was open - Power / Fuel Pump Circuits
Look for power at the fuel pump - the fuel pump has a connector at the rear of the car with a pink/black wire and a black wire that goes to the fuel pump. The pink/black wire should be hot when jumpered to the test position. . To trick the fuel pump into running, find the ECC test connector and jump the connector in the lower RH corner to ground. http://www.mustangworks.com/articles/electronics/eec-iv_codes.html for a description of the test connector. it. No voltage when jumpered, check the fuel pump relay and fuse links.
 

86T-Top

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Jun 29, 2001
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Dublin, PA
Nov 18, 2004
#5
  • Nov 18, 2004
  • #5
To do an update, I took care of code 18C. I found the resistor and it was no good. Anyway just so you guys know the resistor is in the main wiring harness back by the master cylinder. Also the outside of the harness is labeled with "Ignition Supresion Resistor" So I put a new resisrote and that took care of code 18C for me.
As for the other codes, I know I need a new VSS but haven't bothered with it yet. And with 96, I just cleared the code and it never came back. I guess it was just one of those things.

Mario
 

HISSIN50

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Nov 19, 2004
#6
  • Nov 19, 2004
  • #6
Mario, thank you for sharing the info on the location of the resistor. always nice when someone shares stuff they find.
 

TrickStang37

New Member
Oct 17, 2004
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0
Nov 19, 2004
#7
  • Nov 19, 2004
  • #7
86T-Top said:
To do an update, I took care of code 18C. I found the resistor and it was no good. Anyway just so you guys know the resistor is in the main wiring harness back by the master cylinder. Also the outside of the harness is labeled with "Ignition Supresion Resistor" So I put a new resisrote and that took care of code 18C for me.
As for the other codes, I know I need a new VSS but haven't bothered with it yet. And with 96, I just cleared the code and it never came back. I guess it was just one of those things.

Mario
Click to expand...
was that the cause of your intermitint performance problems?? i need ideas for my car, ive had a miss now for a couple weeks, cant find out what it is.
 

86T-Top

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Jun 29, 2001
553
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Dublin, PA
Nov 19, 2004
#8
  • Nov 19, 2004
  • #8
I think it was. The car feels a lot stronger now, but I guess it could be my imagination. But I can run 89 octane gas again, w/o detonation, b4 I was forced to run 93. I'm not really sure what that cirrcuit does, but I have a feeling it does something with adjusting the timing.

Mario
 
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