The 1979-2004 Mustangs use a cable operated clutch mechanism. The quadrant is attached to the upper part of the clutch pedal arm. It made of plastic and has a ratcheting self adjusting mechanism. The plastic ratchet parts sometimes strip and cause problems getting the clutch to disengage. The standard plan is to replace the plastic parts with metal parts of your choice. I recommend that you buy all of the metal parts from the same manufacturer so that they work in harmony with each other. Steeda, Maximum Motorsports, Ford Racing and UPR all make quadrant replacement kits. Do a Google search on the brand names to find the Web sites and catalogs.
The temporary fix for the clutch quadrant is to reach down and pull up on the clutch pedal. This rachets the self adjuster and tightens the cable. If the quadrant ratchet mechanism is bad, this doesn't work.
Don't replace the computer or wiring harness until you have spent some time troubleshooting the stuff you have. Computers seldom fail, it is usually a sensor or wiring problem. The Speed Density system that came with the 86-88 Mustangs is good for cars without pressurized induction, big cams or aftermarket heads. You only need a Mass Air conversion if you have these items or plan on adding them in the near future.
Here's a book that will get you started with how the Ford electronic engine control or "computer" works.
Ford Fuel Injection & Electronic Engine Control 1988-1993 by Charles Probst :ISBN 0-8376-0301-3.
It's about $25-$35 from Borders.com see
Amazon.com: Online Shopping for Electronics, Apparel, Computers, Books, DVDs & more . Select books and then select search. Use the ISBN number (without dashes or spaces) to do a search
Use the ISBN number and your local library can get you a loaner copy for free. Only thing is you are limited to keeping the book for two weeks. It is very good, and I found it to be very helpful.
If you need some help with your automotive electrical skills, try
Automotive Online Instruction for a beginning course. The course is very good and best of all, it is FREE!!!
If you have a mass air conversion, disconnecting the computer will set the code 66. If no code 66 with the mass air sensor disconnected, then someone stuck a mass air meter in there for decoration.
See
http://www.ttcautomotive.com/English/onlineorder/product.asp to download a FREE service manual for T5 or Tremec 3550/TKO
You will need the Adobe Acrobat viewer which is also a free download –
http://www.adobe.com/products/acrobat/readstep2.html
See
http://www.hanlonmotorsports.com/ or
http://www.ddperformance.com for parts
A T5 rebuild kit with syncros, bearings and other small parts costs about $160-$200. It does not include any gears or shafts.
http://www.hanlonmotorsports.com/ also has a video on how to rebuild your T5 or Tremec. It costs about $20, and is worth every penny of it.
Dumping The computer diagnostic codes on 86-95 Mustangs
Revised 19-May-2009 to update drawing for dumping the codes on 86-88 Mustangs with no check engine light.
Dump the codes and see what the computer says is wrong…
Codes may be present in the computer even if the Check Engine light isn’t on.
Here's the way to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.
Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes.
Dumping the Engine Running codes: The procedure is the same, you start the engine with the test jumper in place. Be sure the A/C is off and the transmission is in neutral. You'll get an 11, then a 4 and the engine will speed up to do the EGR test. After the engine speed decreases back to idle, it will dump the engine running codes.
Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.
See
Troublcodes.net Trouble Codes OBD & OBD2 Trouble Codes and Technical info & Tool Store. By BAT Auto Technical
If your car is an 86-88 stang, you'll have to use the test lamp or voltmeter method. There is no functional check engine light on the 86-88's except possibly the Cali Mass Air cars.
The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.
89 through 95 cars have a working Check Engine light. Watch it instead of using a test lamp.
The STI has a gray connector shell and a white/red wire. It comes from the same bundle of wires as the self test connector.
WARNING!!! There is a single dark brown connector with a black/orange wire. It is the 12 volt power to the under the hood light. Do not jumper it to the computer test connector. If you do, you will damage the computer.
What to expect:
You should get a code 11 (two single flashes in succession). This says that the computer's internal workings are OK, and that the wiring to put the computer into diagnostic mode is good. No code 11 and you have some wiring problems.
Codes have different answers if the engine is running from the answers that it has when the engine isn't running. It helps a lot to know if you had the engine running when you ran the test.
Trouble codes are either 2 digit or 3 digit, there are no cars that use both 2 digit codes and 3 digit codes.
Alternate methods:
For those who are intimidated by all the wires & connections, see
Actron® for what a typical hand scanner looks like. Normal retail price is about $30 or so at AutoZone or Wal-Mart.
Or for a nicer scanner see
Digital Ford Code Reader (3145) – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $30.
