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mustang wont start

  • Thread starter Thread starter dany5.0
  • Start date Start date Nov 8, 2004
D

dany5.0

New Member
Aug 26, 2004
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Nov 8, 2004
#1
  • Nov 8, 2004
  • #1
I have a electrical problem I dont have spark I checked the coil no power in to i checked the module no power in to either I start having this problem sense my friend put the alarm I think he cut a wire or something please help me with some wiring diagram for a mustang 5.0 88 thank's
 

88stangmangt

Active Member
Nov 25, 2003
2,332
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Stafford,VA
Nov 8, 2004
#2
  • Nov 8, 2004
  • #2
you sure the alarm isnt useing juice killing the batt? take the neg off you batt and use a volt meter with the IGN off to see if something is pulling on it...
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Nov 8, 2004
#3
  • Nov 8, 2004
  • #3
see Tom's pics at
www.veryuseful.com or autozone's site for schematics.

does the car crank, but not start (catch)?

i would find your friend and see what he did. many alarm installers get an ignition wire from under the lower column cover (there are a couple there).

ask your friend how he wired the starter kill up. most people use a passively wired relay, but you never know what happened. but if it cranks, that is not the issue. some people use an ignition cut off rather than starter kill though.

good luck.
 

4dStang

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Oct 23, 2002
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Near St Louis, Missouri
Nov 8, 2004
#4
  • Nov 8, 2004
  • #4
You say there is no pwer to the coil. Does that mean the car cranks but won't catch? We need more info to help.

 

jrichker

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Nov 8, 2004
#5
  • Nov 8, 2004
  • #5
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
G.) Ignition switch - look for 12 volts at the ignition coil red/lt green wire.
H.) Computer

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
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
 
D

dany5.0

New Member
Aug 26, 2004
15
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0
Nov 8, 2004
#6
  • Nov 8, 2004
  • #6
yes the car cranks but I dont hear the fuel pump coming on and I have no juice on coil wires neither on module wires, i check the eec power relay and im geting power only on one wire which is black and light green...
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Nov 8, 2004
#7
  • Nov 8, 2004
  • #7
go through JR's post and check stuff out.
i could be wrong, but my take:
per Tom's schematic ( http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif ), the black/lt grn wire should be a GROUND. i would troubleshoot those wires in the EEC relay socket.

good luck.
 
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