i was looking over the wires in the engine compartment and noticed that the white ten pin connector had a wire disconnected from the bottom part of of the connector, the color is straight orange, no stripes in it, does anyone know what the orange wire is for and what the connector is called? i checked out the link on jcassity's post for the 1987 wiring diagrams, and it dosent say much about it.
i did check it with a light tester while the engine was idling, tested both + and - no current either way....
Which connector?
(http://mysite.verizon.net/vzetk5cc/sitebuildercontent/sitebuilderpictures/EngineWiring5L.jpg)
its the orange wire on the one labeled c477
I had that one on mine to I ran it to ground.the oxy sensor ground wires are orange.
did it make any difference when you grounded it?
Not that I could tell.
you will find the connector and the wire starting on or around page 55 forward. there you will see the eec pin outs for the 3.8, 5.0 and the 2.3.
seems to me that no ox sensor would singal a rich condition. In an SO application, its not really all that big of a deal i suppose. In a MAF application, its more important from what i understand. V8demon has all this stuff logged into memory, he'd be the one to know it of the top of his head how important it is.
I'm not sure if just one disconnected would cause the ECU to switch to open loop.
I believe it would go into FMEM.
http://www.fordfuelinjection.com/?p=31
FWIW, anybody got the wiring diagram for the (2) 10 pin connectors they can post all big and readable?
I should add that my sensors were already grounded at the back of the heads, also by orange wires.
Hmm. Looking at some wiring diagrams, I wonder if that wire is redundant....
So far as I can tell no wires within the actual HEGO harness are orange...
Here's a link when I asked a while ago.
http://www.foxtbirdcougarforums.com/showthread.php?t=15808&highlight=orange+wire
! I posted in the other link by accident!
Oh well, here it is again, sorry :
http://www.foxtbirdcougarforums.com/showpost.php?p=242454&postcount=14
It could be. I think they eliminated it, and just taped it off to the harness.
Refering to the picture in post #3:
I was only able to locate 7 wires for C477 in the 87 EVTM. None of them orange.
The orange ground wire for the right EGO is G214 in the picture. It has a ring terminal and is grounded to the back of the head.
According to the EVTM it goes through connector C429 and from there directly to pin 49 of the EEC.
The left EGO ground wire is G213. It is a GY/R wire that also goes through C429 and from there to pin 44 of the EEC.
The EGO ground wires do not actually hook to the EGO.
The bottom part of C477 and C475 go to the EEC, the top part to the engine bay.
Do you see a wire in the top part of C477 to match up with the orange wire in the bottom part ?
The EGO sensor generates its' own little voltage, like a little battery.
The positive side of this "little battery" is hooked to a wire that goes to the EEC.
The negative side is the threads that screw into the exhaust manifold.
So the negative (ground) circuit for the EGO is the EGO threads, the manifold, the head and the orange wire to the EEC.
The purpose is to provide a low resistance ground for this low voltage and low current circuit.
If it wasn't there would it find another way? Probably through the engine block, battery cable etc.
Would it be as good? No.
double post. It takes so long to post I think I forgot to hit the submit button.
Interesting.....I haven't peeled back my harness to look, but I did take note of one thing when I looked under my car.....I have no #19 in the main harness diagram. Both of my HEGO sensors have grounds from their respective harness. Another ground comes off the firewall to the back of the intake manifold...I can't see where one of the ground wires on the HEGO harness ends.....I'll look further later.
I also noticed 6 wires going into the HEGO harness on a connector that can accept 8 pins......the other 2 ports are blocked off....
The only time I've ever gotten a HEGO code was a lean code 3 years ago running 19 pound injectors with the pressure too low when I first put this motor back together......
Who wants to bet that I'm missing this wire?
I see there is only one HEGO ground wire in your cable diagram. Maybe when they went from one HEGO to two they just cut wire 19 off and put it all into the HEGO harness.
The heater wires are spliced so they only need two wires in the harness.
(http://mysite.verizon.net/vzetk5cc/sitebuildercontent/sitebuilderpictures/HEGO.jpg)
C477 sources many wires of essential EEC functions like the MAP, TPS, IAC, ECT ect.
There is an Orange / white wire.
double check you do not have a dotted or stripped white tracer on that orange.
Im not sure what the o2 sensors have to do with any of this but I see no relationship so far.
Unwrapped the harness. Guess what? My orange wire is cut! THe piece from the connector is about 5 inches long......No sign of anywhere or anything that it should be connected to. One could surmise it went to #19 on the diagram I posted at one point in time....
Your hypothesis makes sense. Interesting that they would just cut the wire like that if this is in fact the case though.
All other wires accounted for and intact ;)
Your a hell of a guy paul,to cut your harness up.That was what I suspected though, that they just cut it, I guess I"ll cut mine back off.
Wasn't too hard. Won't take too long to tape back up either. I just put some of that plastic tubs sheathing on it for now.
I was actually wondering if it would actually be better to leave it as a safeguard. You just went to the back of the head with it, correct?
No not really, ran it the throttle body, I think it's a dead end wire. so I don't think it would matter.
CONFIRMED
#19 in the harness diagram is in fact the orange wire from the white 10-pin connector.
From my swap, I remember a wire or two in the 5.0 harness that went to nowhere(couldn't remember color)... Unlike Paul, I wasn't going to dig back into my harness...
Hat's off to Paul...
FWIW after some reading on the subject, I'm on my way to the parts store. I'm gonna rebuild that wire and attach it to the back of one of the cylinder heads.
For the right HEGO(passengers' side) the wire goes from the right head to EEC pin49. Orange wire.
For the left HEGO, from the left head to EEC pin 44. Gray/Red wire.
Are you sure the wires are not already there through the HEGO harness? Have you checked the EEC end of the harness ?
If I understand you correctly, there is an orange wire in the bottom side of the white 10 pin connector that ends a short distance into the harness. That bottom side harness goes to the EEC.
What does that orange wire connect to in the top part of that 10 pin connector. Probable nothing.
Yup you got it... They've only been that way for 20+ years, no need to go messin' with it now...
Lots of info on a orange wire!!.
Funny you mention this.....
More poking around...Found the passenger side HEGO ground hooked up properly to the back of the block....Driver side --- Hmm. disconnected (buried under the trans tunnel too).
Dug it out, hooked it up went for a drive.....All normal until the car was running for 5 minutes...Ran like hell after that for about a minute @ idle and under load as well as an attempt @ WOT....
Went away about 2 minutes later.....
Unhooked the ground. Let car sit for 3 hours. Went for drive. Problem gone. I pulled plugs. A little on the white side, but that's more a timing issue -- nothing detrimental (backed the timing back down to 12* BTDC which I'd been meaning to do for a while -- had it @15.)
FWIW when I had the timing @ 12 in the summer and checked the plugs back then they were perfect.
Changed the converter last year. Didn't pull any wires then other than 1 ground from the bellhousing. Haven't had a look at that HEGO ground since early '06 when the motor went back in.
So tell me? Is it possible I'm in constant open loop? Considering how well the car runs and the gas mileage I get while at a steady cruising speed, I find that hard to believe....Especially considering that When I played with my fuel pressure back then, the codes went away...Negative.....It's the TOP side that goes to the EEC....Bottom side branches out to all the connections under the hood TPS, injectors, IAC, EGR, etc. as shown in the diagram. The side that is cut goes to my block. That dead end wire goes to the connector and has a corresponding mate that goess to the main harness and into the firewall...THAT part of the wire is there and does indeed feed into the firewall.
So Paul are you saying that wire actually is goin somewhere?
Or are you putting it somewhere.
I believe the orange wire goes to pin 49 on the ECU 60-pin connector. I know it goes into the firewall.
Dug out my tester today too. Couldn't get it to read.....Nothing in KOEO or KOER. By the looks of my connector I'm guessing it needs a good cleaning, however when I hook it up there is a light that is supposed to come on and it does.....THAT light is supposed to blink with respective codes.....NOTHING. No solenoid/actuator noises either.
My friend has one of those nice Snap-On testers @ his shop. Guess I'll spin by there after work when he opens up and confirm that issue......
Jeez, it just gets worse and worse.
Still wondering if I'm in open or closed loop. I'll know more tomorrow. Until then -- any thoughts on the issue?
BTW to the original poster -- I thank you. Without this thread I would have remained ignorant to the situation with my own vehicle. I hope we've answered some of your questions. I hope I get the answers I'm looking for as well ;)
http://fordfuelinjection.com/?p=85 perhaps this will benifit
Thanks, but that's old news to me :o sorry. I
DO appreciate it though.
New development.....I've duplicated the effect with the grounds disconnected as they were when I started this.....
I've hooked all grounds up as they should be from Ford.
Got the code scanner to work. Other than the codes I knew I would get for items that no longer exist on my vehicle there was one that stuck out JUST a bit
Code 85
canister purge solenoid / adaptive lean limit reached in fuel control programThe way I typed it is exactly how it read on the Snap-On LCD screen. The first part.....well I SHOULD get that for reasons I'll not get into - and that is not cause for driveability issues.......The second.....disturbing.....I bumped the pressure back up to 48. She was happy there before so.....
Essentially what I've learned is that the ECU is in fact going into closed loop, but for some reason it now does a 30-45 second "shake your booty" dance before it gets there and is still a little choppy under no load/light load conditions after that. Heavy load and WOT are fine.
I have a couple of ideas...
I'll let you know what happens ;)
You know I bet this wire is hooked up on my car. Thanks to you guys I'm going to go digging into my harness this weekend to find out :hick:
Bet you it's not!!, I have an old harness from a stang, both of the white and black. there is no orange on one side but on the other there is "cut and taped". And paul that is one hell of a scanner that tells you adaptive stragety problem. Does it tell you how to cure it ?
No. But pulling the HEGO harness connector while the engine is known to be warm enough for closed loop alleviates all issues....
The sensors MAY be reading the wrong banks....It's too dark for me to see the colors right now right now....Have to wait till daylight. Still hard to believe that the car was in open loop and never gave indication of HEGO codes.....
i feel like i opened a whole can of worms with this thread:D
ok,, im lost,, as usual.
the orange wire shows up on the evtm per my previous post.
now pretty much all of you are saying its flopping in the wind?
Im gonna have to check mine also.
i pulled one from a 5.0 t - bird around the same year and the same orange wire seemed to be disconnected also, maybe just a coincidence?
I don't believe it's coincidence......Here's why:
Here's the main engine harness as it sits in a MUSTANG
(http://i280.photobucket.com/albums/kk191/V8Demon/Car%20Stuff/mustangEngineHarness.jpg)
(http://i280.photobucket.com/albums/kk191/V8Demon/Car%20Stuff/mustangEngineHarness.jpg)
Now here's the MUSTANG HEGO harness:
(http://i280.photobucket.com/albums/kk191/V8Demon/Car%20Stuff/mustangO2Harness.gif)
That HEGO harness has some differences compared to the one in my car......
1) I have ground wires on each o2 connector. That one does not.
2) The wire colors in the picture do not correspond to what I see under my hood
3) That wire harness has a part # beginning with E8......
My hypothesis:
There are TWO (2) different HEGO harnesses......
Depending on which one was installed -- which was most likely through the vehicle type -- foretold whether or not the orange ground in the main engine harness was cut or hooked to the block. I realize there are different part #'s for auto and manual cars, but from what I understand, the difference is the main connector -- it varies from auto to manual cars.....
See here:
(http://i280.photobucket.com/albums/kk191/V8Demon/Car%20Stuff/harness03.gif)
Take note of the black connector -- the one I have. The only one with a HEGO ground wire provision ;)
Tomorrow I'll be swapping the o2 connectors to the opposite o2's......
I'll keep you posted ;)
let me know what happens man
Ready kids?
(http://econtent.autozone.com:24991/znetrgs/repair_guide_content/en_us/images//0900c152/80/06/bb/cb//large/0900c1528006bbcb.gif)
Now if you'll look at pins #43 & #29 you can see the wire colors.....
Softtouch posted this in post #19 as well via the EVTM. Big thumbs up to him. I found it easier to read this though....and finally understood what he was getting at.
FWIW -- my sensors are indeed reversed......Redid the exhaust in September of last year....Was done by a shop that had to weld in the o2 sensor bungs. The limited driving of the car this past year -- maybe 2000 miles this past year -- and the fact it ran very well while in open kept me in the dark. When it stops raining I'll swap them.
Looks like my issue is solved -- just awaiting good weather.
[SIZE="7"][COLOR="Red"]Fixed!!![/COLOR][/SIZE]
:burnout: :burnout: :burnout: :burnout:
any improvement in driveability?
That's what fixed means ;)
No more chugging/hesitation in closed loop. Clean and smooth.
Ok well im not exactly trying to dig up an old post, but i feel what im about to ask is better said in this post than a new one. V8 demon said
And after he fixed them....
Now my question is if the 02 sensors are unhooked completely (Installed exhaust myself, havent gotten the o2's welded yet) would this also make the motor choppy/hesitant under light load? It runs better under heavier loads and WOT and still gets about 23 - 28 mpgs
It will affect how your engine runs, I find it hard to believe you get 28 mpg with them unhooked, Maybe I'll go pull mine!
Well i bought the car in Florida and drove it back here to Tennessee where i live and thats about the mileage it got. When i bought it, the exhaust was all chopped up where it had been rusted ( the car was originally from Ohio - go figure lol) and the o2 sensor wires were cut. It drove without any major problems but it was VERY hesitant under light load
If you set the car up properly, it's possible. You'd have to pay attention to what you were doing, get lucky, or a little of both. The ECU does not use the readings from use readings from the o2 sensors @ WOT FWIW. THe o2 sensors are used for varying load/rpm conditions to increase gas mileage and reduce emissions under light and moderate load conditions.
Without them and with a good understanding of the fuel system and the right components you can basically tune the car. It's gonna take some trial and error along with a code reader though (at the VERY least). Similar to changing jets on a carb if you think about it. You'll never have the versatility that the adaptive strategy coupled with the o2's will give though...
well im gonna get the o2 sensors hooked back up im just trying to troubleshoot to find out why my engine is running like sh*t
Like v8 said, Either tune it without them or get them hooked.
If you hook them up your car might run better. You really can't complain how it runs till you make the effort to make it right.
Oh im not complaining, just trying to rule some stuff out. Appreciate the info guys.
I had NO warning....NONE no hesitation, bucking, driveability issues....NOTHING. The car even got decent (as in 20+ HWY) gas mileage. It was dialed in rather well.
I have this same problem, my orange wire seems to have been cut. Did any of you ever figure this out?
So did we actually establish what this orange wire is for? Mine is cut as well, I'm just curious.
Yes. It's redundant in the system and replaced by the dual grounds on each of the HEGO connectors. It's all in the thread.
alright, i was reading one of your posts and it said when you connected one of the HEGO sensors the car ran different, I got a little confused and figured I just better ask...
Is it worth taking the time to ground it out?
Different issue, but along the same lines
Not really.
I'm not sure if anyone remembers the bout I had getting my car to START after my HO top end swap.
There was an orange wire, just like this...same deal. Seemed cut, I figured it broke when I pulled the intake or something and forgot to disconnect it. Don't think so though.
I NEED this wire....once I grounded it the engine started. Without it grounded...nothing at all. No sputtering...the injectors wouldn't fire I suppose, because spraying carb cleaner into the intake made it start, and run until that was used up.
Wonder why I now need it with H.O. as opposed to not needing it with S.O....
1. Which ECU are you running?
2. Does your HEGO harness have grounds on it?
3. Are the other body grunds for the car present and in good condition?
Currently a Mustang 5spd computer....but it WAS a mark vii auto comp originally. I do believe the hego harness DOES have it's own ground....which, I think this one actually WAS...because I found diagrams back then and what I thought was odd was that the wire was said to be "Oxygen Sensor Harness Ground"....when the sensors themselves each had a ground that was bolted to each cylinder head.
AFAIK anyway...the grounds that I know of are good. That braided strap near the brake booster is all fine, was sure to check that one back then kinda more semantics than anything.
Your oxy. sensors ground should be bolted to the back of the head. The orange wire everyone seems to find isn't even redundant, It's just not used, at least on my car.
Yes there are two of em, each one comng out of the wire looming wrapped around each oxygen sensor's plug (the harness side of things). The wire has a loop terminal on the end of it and is separate from the other four wires, which naturally go to the sensor plug. And that is grounded to the head, for each sensor.
Good thing I just thought of it! Good name they have for the site..stuck in my mind. http://www.veryuseful.com/mustang/tech/engine/images/mustangEngineHarness.gif
In that diagram, number 19 I think is what were talking about, and it's the one that was broken on my car, and once grounded, allowed the car to start. It says "HEGO Sensor Ground".
It's well known that oxygen sensors aren't even needed for it to run, albiet terribly. That was what made me ignore them for the most part way back when...didnt make sense that they could make it not even fire. Yet once I stripped that wire (very short so I could barely do it) and spliced in another and grounded it, it started.
obviously HEGO are the o2 sensors, but what does HEGO stand for?
Heated Exhauss Gas Oxygen sensor. Two of the wires are for the heating element. Helps to get it up to temperature quicker and get a reading ASAP after the engine is started.