Electrical harness ground?

ColdAudio

New Member
Jan 9, 2006
31
0
0
Hey guys, I'm having a problem with the car (as usual) :). I'm wondering, what function do the two cylinders with a harness coming out of them on the firewall side of the intake manifold serve? Mine move around quite easily and the cars idle and electrical jump with the slightest shift of them, I know alot of my electrical stuff doesn't work right like temp gauge inconsistency, no heat because of electrical problem, signals not always working because of something with the ignition where the key is, among other things? How may this item tie in? Thanks
 
  • Sponsors (?)


i assume you mean the "salt and pepper" shakers as their called. a white one and a black one.

those go to the injectors and some other stuff im not familiar with.

can you tell if there is a extension wire inbetween? ford originally had them connected, then they thought there was not enough slack in them under the engine moving and they put extention wires inbetween......so you'll see the one connection right their where their attatched to the upper manifold, and then another connection several inches behind that if they have the extesion wires
 
Ahh thanks a ton for the replies, i dont have the extended harness but saleen that link is awesome thatll be my project as soon as it stops snowing as im sure that will be the problem, the wiring harness is so damn old! I've got another question which may or may not be related.

In order to get the four dummy lights (low gas, low oil, etc.) to turn on when I start the car so the computer is working at its correct settings (to make vents work, signals work, etc.) I have to wiggle around the key and ignition ALOT for a minute or two. Is there any fix for this? I'm unsure of what to use for a search term to find old threads that may be related. Thanks a bunch for the help everybody, I appreciate it.
 
ColdAudio said:
Ahh thanks a ton for the replies, i dont have the extended harness but saleen that link is awesome thatll be my project as soon as it stops snowing as im sure that will be the problem, the wiring harness is so damn old! I've got another question which may or may not be related.

In order to get the four dummy lights (low gas, low oil, etc.) to turn on when I start the car so the computer is working at its correct settings (to make vents work, signals work, etc.) I have to wiggle around the key and ignition ALOT for a minute or two. Is there any fix for this? I'm unsure of what to use for a search term to find old threads that may be related. Thanks a bunch for the help everybody, I appreciate it.

The ignition switch is probably going bad.

There is a FREE recall on Ford ignition switches. They overheat and sometimes catch fire.

Copy down you VIN number and call the Ford dealer nearest you. Tell them you want to see if the ignition switch recall for Fords & Mustangs was done on your car. They will ask for the VIN number & check it against the master database. If it isn't in the datbase, then you can schedule an appointment to have the switch replaced for free. The TSB is #95S28, and don't let them tell you that they don't do that anymore...
 
jrichker said:
The ignition switch is probably going bad.

There is a FREE recall on Ford ignition switches. They overheat and sometimes catch fire.

Copy down you VIN number and call the Ford dealer nearest you. Tell them you want to see if the ignition switch recall for Fords & Mustangs was done on your car. They will ask for the VIN number & check it against the master database. If it isn't in the datbase, then you can schedule an appointment to have the switch replaced for free. The TSB is #95S28, and don't let them tell you that they don't do that anymore...

Thanks a bunch jrichker I'll stop by Ford on the way to work!
 
Alright so I took apart the connectors, they were full of gunk and dirt and all that fun stuff, thorougly cleaned them then put a small amount of di-electric grease... put it all back together and.... lucky me I get a CEL. Pulled codes 98 and 64 with the car running. Any ideas what would cause this/what these codes mean? thanks
 
Code 98 - basic computer internal tests not passed before
it started processing the request to dump codes. Do a Key
On Engine Off test before starting the engine. Wait until
you see the 11 flash before pressing any buttons if you
have a hand operated scanner. The computer is operating
in Limp mode, so fix any codes it dumps prior to doing
anything else.

Code 64 – ACT (Air Charge Temperature) signal low or
grounded. Bad sensor, sensor wiring on pin 25 shorted to
ground, or bad computer.

Note that all resistance tests must be done with power
off. Measuring resistance with a circuit powered on will
give false readings and possibly damage the meter.



The ACT is located in the #5 intake runner on Mustangs
built from 86-93. Disconnect the sensor by removing the
sensor wiring connector. Measure the resistance across the
sensor pins.

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

If the sensor resistances read good according to the table,
remove the passenger side kick panel and disconnect the
computer connector. A single 10 MM bolt secures the
connector in place. With the sensor connector still
disconnected, measure the resistance between pin 25 (lt
green/pink wire) and ground. If you wish, you can make
your measurements at the ACT sensor end. This will save
you from counting the computer connector pins to locate
the correct one. However, you will still have to disconnect
the computer connector. You should see 100K Ohms or
greater between pin 25 and ground. Less than that
indicates wiring problems with the pin 25 lt green/pink wire
shorted to ground. Note that the following diagram on the
connector displays the pins viewed from the computer side.

eec04.gif


See 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/

http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif

Diagram courtesy of Tmoss & Stang&2birds

88-91eecPinout.gif


If the resistance readings for the ACT sensor and the ACT
wiring on pin 25 read OK, then you have a bad computer.
Do not replace the computer unless the two test steps I
have described pass OK. Computers seldom fail and are
very rugged. It takes a lot to kill one while it is bolted in
place in the car.
 
Hey sorry it was a typo on my part I actually pulled a 98 and 63 with the car running. 63 is TPS sensor so I replaced it, still pulls the code even after resetting computer. With the key on engine off, I'm pulling 31,63,85 ..... why all of the codes all of the sudden after cleaning out the salt and pepper shakers? What could cause a TPS code if the TPS wasn't bad? Any ideas on the other codes? Thanks.
 
I couldn't get the male fittings to spread apart but I did push the female fittings closed more for a better fit and did lube the connections. Is there any fix to this problem? Is it possible for me to pick up the extension harness Ford made anywhere? Any way to make the connection tighter?
 
CODE: 31 (KOEO) - EVP circuit below minimum voltage. Vref (5 volt reference voltage supplied by the computer) missing or broken wire or bad connection in circuit. Use a DVM to check for 5 volts on the orange/white wire. If it is missing, look for +5 volts at the orange/white wire on the TPS or MAP sensor located on the firewall near the center of the car. Use the black/white wire for the ground for the DVM.
With the sensor removed from the EGR and still connected, press the plunger and watch the voltage change on the brown/lt green wire. Pull the passenger side kick panel and measure the voltage at the computer. You will need to remove the plastic cover over the wires and probe them from the backside. A safety pin may prove very useful for this task. Use pin 27, EVR input (brown/lt green wire) and pin 46, signal ground (black/white wire) to measure the voltage. The orange/white wire is Vref and should always be 5 volts -/+ .25 volt. Be sure to measure Vref at the EGR sensor to rule out any broken wires or bad connections.

Code 63 - Throttle Position Sensor (TPS) signal too low TPS . TPS out of adjustment, or 5 V VREF missing, broken wiring or bad connections.

Check the Orange/white wire for 5 volt VREF. It should be 5 volts +/- .25 volt. No 5 volts and you have wiring problems.

Try this... Currently there is some dispute about setting it at .99 volts being worth the effort, but anything less is probably OK. All you need is less than 1.0 volt at idle and more than 4.25 at Wide Open Throttle (WOT). You'll need a Digital Voltmeter (DVM) to do the job.

Wire colors & functions:
Orange/white = 5 volt VREF from the computer
Dark Green/lt green = TPS output to computer
Black/white = Signal ground from computer

Always use the Dark Green/lt green & Black/white wires to set the TPS base voltage.

Use the Orange/white & Black white wires to verify the TPS has the correct 5 volts source from the computer.

Here’s a TPS tip I got from NoGo50

When you installed the sensor make sure you place it on the peg right and then tighten it down properly. Loosen the back screw a tiny bit so the sensor can pivot and loosen the front screw enough so you can move it just a little in very small increments. I wouldn’t try to adjust it using marks. Set it at .97v-.99v, the closer to .99v the better.

(copied from MustangMax, Glendale AZ)

1. Always adjust the TPS and Idle with the engine at operating temp. Dive it around for a bit if you can and get it nice and warm.

2. When you probe the leads of the TPS, do not use an engine ground, put the ground probe into the lead of the TPS. You should be connecting both meter probes to the TPS and not one to the TPS and the other to ground.

3. Always reset the computer whenever you adjust the TPS or clean/change any sensors. I just pull the battery lead for 10 minutes.

4. Check the procedure for your year, on my 90 I have to turn the idle screw until it just touches the tab, then insert a .010 feeler gauge and give it about one more turn. Then you adjust the TPS voltage to .98v, reset the computer. Start it up, if the idle is to low then turn the screw in until it is just right, then readjust the TPS voltage to .98v and reset the computer and start it up. The key is to adjust the TPS voltage and reset the computer whenever the idle screw is changed.

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.