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Starting Problems after sitting a couple of weeks!!!!

  • Thread starter Thread starter MY90GT
  • Start date Start date Jul 14, 2005
M

MY90GT

Founding Member
Mar 12, 2000
201
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0
Louisville, KY
Jul 14, 2005
#1
  • Jul 14, 2005
  • #1
OK, I'll try and make this short and sweet. Car has been down a couple of weeks while I replace all the A/C components on the car. Had to drop the steering wheel, dash and remove the HVAC unit to replace the evaporator core and heater core. Took pictures and great care on disconnecting and reconnecting wiring harness, and anything else that had to come loose. Everything has been reassembled, and the A/C united vacuumed down but not charged yet. OK, now the problem. After I got everything back together, started the car, no problems.
The next day, wouldn't start, will crank, start sometimes, not start sometimes. If
I go to WOT, sometimes will start, rev, then die, sometimes start no problem. No error codes.

ANY IDEAS ????????
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jul 14, 2005
#2
  • Jul 14, 2005
  • #2
when it wont stay running, do you have spark? How is FP? That would give folks an idea of where to look.

This just happened to my buddy (he said it felt like it was trying to run on one cylinder when it caught for a split second, then died). Bad FP.

Good luck.
 
M

MY90GT

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Mar 12, 2000
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Louisville, KY
Jul 15, 2005
#3
  • Jul 15, 2005
  • #3
FP ? Fuel Pump.
What should my fuel pressure be?
 

jrichker

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Jul 15, 2005
#4
  • Jul 15, 2005
  • #4
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.) Coil
B.) TFI module
C.) PIP sensor in distributor
D.) ECC relay next to computer
E.) Fuse links in wiring harness
F.) Ignition switch
G.) 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.
C.) Clogged fuel filter
D.) Failed fuel pump
E.) Blown fuse link in wiring harness.
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 Noid light available from Autozone, is one way to test the injector wiring. 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 form the non HO engines.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Jul 15, 2005
#5
  • Jul 15, 2005
  • #5
MY90GT said:
FP ? Fuel Pump.
What should my fuel pressure be?
Click to expand...
Both. FP = Fuel pump when there is a 'the' in front of it.
And it is fuel pressure when there is no 'the' in front of it.

FP with vac line off and capped is ~39 PSI. Once the vac line is reattached, 30+ PSI should be good to go.

Good luck.
 

normster6969

Founding Member
Oct 6, 2000
558
4
18
Huntington Beach, CA
Oct 3, 2005
#6
  • Oct 3, 2005
  • #6
Thanks for the great checklist!

jrichker said:
Cranks OK, but No Start Checklist for Fuel Injected Mustangs

1.) Remove push on connector ...
Click to expand...


I realize this is an old post but I just wanted to compliment you with the best rundown for trouble shooting a no start situation. I have the OEM ford DVD and it's horrible trying to follow their troubleshooting pinpoint tests. Your layout and plain english translations are awesome. I'll have a print out next to me when I start trying to figure out my POS.

Thanks!
 
M

MY90GT

Founding Member
Mar 12, 2000
201
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0
Louisville, KY
Oct 3, 2005
#7
  • Oct 3, 2005
  • #7
Amen Brother
 
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