Screwed up my mustang need help quick!!!

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Cranks OK, but No Start Checklist for Fuel Injected Mustangs

1.) Remove push on connector from starter solenoid and turn ignition switch on. Place car in neutral or Park. Remove coil wire from distributor & and hold 3/8” away from engine block. Jumper the screw to the big bolt on the starter solenoid that has the battery wire connected to it. You should get a nice fat blue spark.
Most of the items are electrical in nature, so a test light, or even better, a voltmeter, is helpful to be sure they have power to them.
No spark, possible failed items in order of their probability:
A.) MSD or Crane ignition box if so equipped
B.) Coil
C.) TFI module
D.) PIP sensor in distributor
E.) ECC relay next to computer - look for 12 volts at the fuel injector red wires
F.) Fuse links in wiring harness - look for 12 volts at the fuel injector red wires. All the fuse links live in a bundle up near the starter solenoid.
G.) Ignition switch - look for 12 volts at the ignition coil red/lt green wire.
H.) Computer

See the following links for wiring diagrams...

http://www.autozone.com/servlet/UiB..._us/0900823d/80/16/71/3c/0900823d8016713c.jsp for 79-88 model cars

http://www.autozone.com/servlet/UiB..._us/0900823d/80/19/59/5a/0900823d8019595a.jsp for 89-93 model cars

http://www.autozone.com/servlet/UiB..._us/0900823d/80/1d/db/3c/0900823d801ddb3c.jsp for 94-98 model cars


2.) Spark at coil wire, pull #1 plug wire off at the spark plug and check to see spark. No spark, possible failed items in order of their probability:
A.) Moisture inside distributor – remove cap, dry off & spray with WD40
B.) Distributor cap
C.) Rotor
D.) Spark Plug wires
E.) Coil weak or intermittent - you should see 3/8" fat blue spark with a good coil

3.) Spark at spark plug, but no start.
Next, get a can of starting fluid (ether) from your local auto parts store: costs a $1.30 or so. Then pull the air duct off at the throttle body elbow, open the throttle, and spray the ether in it. Reconnect the air duct and try to start the car. Do not try to start the car without reconnecting the air duct.
Two reasons:
1.) If it backfires, the chance for a serious fire is increased.
2.) On Mass Air cars, the computer needs to measure the MAF flow once the engine starts.
If it starts then, you have a fuel management issue. Continue the checklist with emphasis of fuel related items that follow. If it doesn’t, then it is a computer or timing issue: see Step 4.

Clue – listen for the fuel pump to prime when you first turn the ignition switch on. It should run for 5-20 seconds and shut off. To trick the fuel pump into running, find the ECC test connector and jump the connector in the lower RH corner to ground. See http://www.mustangworks.com/article...c-iv_codes.html for a description of the test connector. If the relay & inertia switch are OK, you will have power to the pump. Check fuel pressure – remove the cap from the schrader valve behind the alternator and depress the core. Fuel should squirt out, catch it in a rag. Beware of fire hazard when you do this. In pinch you can use a tire pressure gauge to measure the fuel pressure. It may not be completely accurate, but you will have some clue as to how much pressure you have.

No fuel pressure, possible failed items in order of their probability:
A.) Tripped inertia switch – Coupe & hatch cars hide it under the plastic trim covering the driver's side taillight. Use the voltmeter or test light to make sure you have power to both sides of the switch
B.) Fuel pump power relay – located under the driver’s seat in most stangs built before 92. On 92 and later model cars it is located below the Mass Air Flow meter. Look for 12 volts at the Pink/Black wire on the fuel pump relay.
C.) Clogged fuel filter
D.) Failed fuel pump
E.) Blown fuse link in wiring harness. Look for 12 volts at the Orange/Lt Blue wire on the fuel pump relay. The fuse links live in the wiring harness near the starter solenoid.
F.) Fuel pressure regulator failed. Remove vacuum line from regulator and inspect for fuel escaping while pump is running.

Fuel pressure OK, the injectors are not firing.

A.) A Noid light available from Autozone, is one way to test the injector wiring.
B.) I like to use an old injector with compressed air applied to the injector where the fuel rail would normally connect. I hook the whole thing up, apply compressed air to the injector and stick it in a paper cup of soapy water. When the engine cranks with the ignition switch on, if the injector fires, it makes bubbles. Cheap if you have the stuff laying around, and works good too.

a.) Pull an injector wire connector off and look for 12 volts on the red wire when the ignition switch is on.
b.) No power, then look for problems with the 10 pin connecter (salt & pepper shakers at the rear of the upper manifold).
c.) No power and the 10 pin connections are good: look for broken wiring between the orange/black wire on the ECC relay and the red wire for the 10 pin connectors.


4.) Spark & fuel pressure OK.

A.) Failed IAB (no airflow to start engine). Press the throttle ¼ way down and try to start the car.
B.) Failed computer (not very likely)
C.) Engine ignition or cam timing off: only likely if the engine has been worked on recently).
D.) Firing order off: HO & 351 use a different firing order from the non HO engines.
HO & 351W 1-3-7-2-6-5-4-8
Non HO 1-5-4-2-6-3-7-8
E.) No start when hot - Press the throttle to the floor & try starting it if you get this far. If it starts, replace the ECT.
 
I would undo everything you did and see if it fixes it.

You can have your TFI bench tested if needed.

And when I did my tach, I used the coil wires, not the TFI wires.

Good luck.
 
hereis a diagram by Tom Moss (site host is S+2B's).

Can you tell which wires on the TFI harness you tapped into - that would help us (well it would help JR, since he is a lot smarter than I am) figure out what could have happened.

The tach signal should have been connected to the negative side of the coil, which does come from the TFI. I dont know which wire you tapped into though.

Good luck.
 
its in the clip that connects to module on distributer ,i think theres 4-6 or so wires. the one i tapped is the green one with the yellow stripe into it.

the tfi module is the gray one that mounts to distributer.
 
whats the solid greenish wire,1rst or second wire from top of clip? my friend also hooked into that but car would still run. thanks for the pics and info ill go check it out :)
 
According to the diagram provided by hissin50, the first wire from the top is the ignition signal 'PIP' out to the computer. My diagram says it is dark blue, but I don't know the year of your car, so I used a 1990, I think. The second wire from the top is the computer timing signal 'SPOUT' to the ignition module. SPOUT is the one with the plug in it, that you pull out to set the timing.
 
car is 88 gt. ok i installed it to the pip out dark blue first i think, tach wouldnt work but car still ran, then to the coil negative wire . then the car would not run /no spark anywhere but fuel pump still turns on
 
88 gt, ok, I checked, the colors are the same. The one you should be using for the tach is second from the bottom I think. But wouldn't it be better to tap the wire at the coil? If that wire is shorted, the coil will charge up but not fire. Maybe your tach is bad.
 
no it dosnt,i opened up the module a couple min ago and see a black line/spot and black on one of the wire things. its in the back lower corner of module. im getting a new one tommaorw i guess, guessing thats the problem

oh and i think im right but gunna ask anyway, if my fuel pump turns on it means my eec power relay near the comp is working correctly right?