[liljoe07]

You will be forced to deal with a code 67. Which will not allow you to access the Computer Diagnostics in that form. Just wire the 02 harness for the trans setup being used.

Auto trans setup would be Purple/yellow wire looped to white/pink wire

Manual Trans setup would be Purple/yellow wire looped to blue/yellow wire.

 

[NJMatt50]

This is the harness for the 86 speed density on the computer side, less wires than the MAF harnesses. You can see that even if you jump the o2 side that you are talking about there is no pins going anywhere to take the jumped signal. In my case why does it matter using the later auto or 5 speed o2 harness??

I am using an A9P. Have not driven the car but my only worry is the "hanging idle" and not being able to pull codes.

 

[Ourobos]

Subscribing

 

[liljoe07]

Ah!!!! I see what you are saying. In that case you would need to ground pin 30 at the computer. This will cancel out code 67 and allow you to run the codes. I remember fighting with the same code years ago. I found my O2 harness didn't have the loop wire. So I'm assuming the guy I bought the car from, used an SD 02 harness. Anyways I just grounded PIN 30 for the time being. I didn't get any idle hang.

 

[NJMatt50]

Ya, I checked the KOEO code 67 came up, cannot run codes KOER. Can't I check the codes with the clutch pedal down? Where does pin 30 go on the mass air harnesses?

 

[liljoe07]

Kinda everywhere.... LoL

Ive never really traced it all the way. But it goes from the computer, to the 02 harness connector and one of the dash connectors. Then to the clutch switch and NGS switch.

Im not really familar with the SD harness's or ECM control. But just from your picture Im guessing that Neutral and In Gear switching wasnt part of the strategy.

 

[keithnra]

i guess i need to check mine also

 

[Eleanor68]

I'm also interested in fixing the hanging idle. My car was an AOD, i left the a9p ecm in, left the O2 sensor harness of course, and ran the correct t-5 extension harness, removed the two jumper plugs up under the dash, and all works fine, except for the idle hang...how do I get that corrected? I have an a9l ecm i could use, but then that requires different O2 harness, or can jumpers be added/moved within that harness to correct everything????

 

[Decipha]

its programmed to do so, can be changed with a chip

 

[Neomustangz]

*THIS IS A COPY PASTE FROM ANOTHER SUBSCRIBED THREAD*

Seen people talking about some 02 harness's and such here on the thread, so i copied and pasted what i wrote with pics.

Heres some pictures below on what to look for when looking at 02 harness's. I have gathered as much data as possible. I can confirm all these 02 harness' from their respectable cars from 87-93.

Lets look at the cannon plug first. Im going to label the 02 cannon plug from left to right from top to bottom. Holding the cannon plugs main clip portion at the 12 oclock position and the slots at the 4 and 9 oclock position. The top 4 pins are 1-4 and the bottom 4 pins are 5-8.

Notice the loop wire on the cannon plug on the below pictures. This loop is different than a 5 speed and AOD transmissions. The 02 harness's ARE different in those aspects. This is the culprit from the signal return trace being burned up. The loop wire we are focusing on are from a mass air 02 harness and or mass air engine harness from an 88-93 (87 is left out because there was not mass air then, and 88 only had california cars that were mass air with 8LD computers). Now sense 87 was left out ill also show a picture of the SPEED DENSITY 02 harness as well.

This is a picture of a speed density 02 harness. NOTICE There is NO loop wire.

This plug is from an AOD Transmission. From what i can tell. there is NO difference between an AOD mass air 02 harness from 88-93. They are all the same. Looking at the back of the cannon plug the wire is looped between pin number 5 and pin number 6

This is a plug from an 87-90 5 speed 02 harness. This pin is looped from pin 1 to pin 5.

And the last of the 02 harness loop wires are from 91-93 5 speed 02 harness's. Notice the loop wire from pin number 1 to pin number 6

so from a tuning standpoint for those with power adders. I have helped diagnosis problems at my local dyno shop for years of fox's. Wanted to mention people that run 87-88 cars that were naturally speed density cars that were still running original wiring and/or that have been either rewired to mass air or an engine harness swap. You will have to swap or repin your 02 harness as well along with the mass air harness as mention above. The software will have problems reading or talking to the 02's if you are going to chip the car on a custom tune. Its a nightmare for tuners and will run your dyno bill WAY up for the hours trying to figure it out.

 

[RACEME]

ok, I have a 92 5 speed car. It came as a roller with no engine harness. I put a complete AOD engine harness/02 harness/a9p computer in it from another 92. It runs fine, but I have a check engine light on. I figure that is because I have no EGR stuff.

Do I need to do anything to the 02 harness or any other wires?

 

[916cali-notch]

Help please I don't understand

Ok guys so reading all this above all I need to do is ground the #30 pin or Put the correct o2 sensor harness in... I need to check what harness I have but I know I put a 88 harness from ecu to engine o2 idk no clue and I'm running a A9p on a 4 cyl swap orig 5 spd I'm running a tremec 5 spd. I want to tune but I haven't yet and I want the ecu to see the o2 sensors can I just jump a ground wire from pin 30?

 

[916cali-notch]

Ok so I got now if I run A9L I need blue/yellow pin 1 to 5 O2 harness or if I use a A9P I need to have a O2 harness or re pin it to purple/yellow pin 5 to 6 that for 88 car with mass air regardless of what trams mission I run the ecu and proper o2 pin configuration must match in order for the ecu to not run limp mode

 

[Blown88GT]

See p. 22, 29, 31
1988 EVTM

 

[916cali-notch]

OK so I know I have a spd density O2 harness because there is no jumpers but according to neomustang i need to run A9L and MT O2 harness to correctly function....I do have the manuel harness from the tunnel to my tremec 3550 5 spd but i now need a o2 harness from a MT or modify my spd density o2 harness and run a A9L ecu Thx for the diagrams but I looked but had no clue what im looking at I think I have a handle on this but I need a conformation that I am right and my o2's will me read and I will be able to tune my car now?...i am getting a code 67 and currently not able to run KOEO running code scan :salute:

 

[Blown88GT]

Connector C107 is what they are referring to as the O2 harness, which it is not. p.25 has a pic of of C107 locations for both transmissions.

The HEGO (O2) connectors are C451 & C452 (see p. 29 & 41). I am unable to determine which one the pics show.

There is no difference in HEGO circuit between SD & MAF. You can see it for yourself on p.29. There is a difference in where the splice is made: S131 vs. S132. The locations of these are on p. 127. Electrically they are the same.

A9L is correct for M/T.

Code 67-NDS Failure

 

[916cali-notch]

Ok now I changed my speed density o2 by splicing the purple/yellow for my A9P. My trans harness is rigged so I can start my car but the Tremec 3550 doesn't have the right hook up switch so there is no point of trying to make that correct.....I started now I have a hanging idle I wish neomustang would chime in on this

 

[SSrunU2]

Yeah Im gonna have to recheck my car. I have a hanging idle. I used a a9l in a m/t '88. Remembering jumping some wire at 50 pin connector. I guess you check pin 46 for voltage while car is cranking No voltage=good to go.

 

[916cali-notch]

i nt have hanging idle but i have check engine light still

 

[rsjohnsn]

Ok, I am seriously confused! I have a '93 that was AOD, I just rebuilt the engine and swapped it over to a T5. I am using the harness and O2's from the auto and I have only started it once long enough to go through a warm up cycle. I'm not sure what ECM I have but I will find out tomorrow. What should I be looking for and have I done any damage with the warm up period?

Thanks
Scott