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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

car won't start after valve cover swap

  • Thread starter Thread starter jstang209
  • Start date Start date Apr 15, 2006
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Apr 15, 2006
#1
  • Apr 15, 2006
  • #1
I swapped my valver covers today which required me to remove the manifold and what not. Newyas I went to fire up after a while so the sealant can dry, and the car started and idle'd around 1.5k for like 30 seconds then it just died and it wouldn't start back up for nothing!! I was thinkin I was out of gas but I put some in and it started for 3 seconds or so then just died again.. I'm stumped!
 

tunedin302

I AM the law!!!
Jul 29, 2004
1,251
2
36
Pennsylvania
Apr 15, 2006
#2
  • Apr 15, 2006
  • #2
Did you touch the distributor. Did you re-set the timing?
 

ALMOST STOCK

Founding Member
Sep 23, 2000
1,250
41
88
CA.
Apr 15, 2006
#3
  • Apr 15, 2006
  • #3
You have checked all the vacuum lines to make sure everything connected ?
 

bill302

Active Member
Nov 2, 2005
2,131
1
46
alabama,gadsden
Apr 15, 2006
#4
  • Apr 15, 2006
  • #4
you double posted...you say you removed the manifold do you mean upper intake and it sounds like you may have an intake or vacuum leak somewhere did you use a new gasket and clean the surfaces properly and inspect vacuum hoses for cracks and install all of them properly.you might want to recheck all the above...
 

TRWXXA

Member
Jan 18, 2003
190
1
19
RIGHT BEHIND YOU!!!... Made you look.
Apr 15, 2006
#5
  • Apr 15, 2006
  • #5
Jeeeeeeezus!! You triple posted this!

If you can't figure out this computer thing, perhaps you should stay away from your 'Stang's motor too.
 

bill302

Active Member
Nov 2, 2005
2,131
1
46
alabama,gadsden
Apr 15, 2006
#6
  • Apr 15, 2006
  • #6
:SNSign:
 
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Apr 15, 2006
#7
  • Apr 15, 2006
  • #7
sorry i was doing it on my sidekick phone and it kept saying an error occured so i kept redoing it lol, btw i didnt use a new manifold gasket but i cleaned it off and used a good amount of sealant. I just got home and tried to start, it wouldnt then i tried again and it started for about 20 seconds then shut off and wont start back up!! man wat could causing this? i jus wana drive my car
 
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Apr 15, 2006
#8
  • Apr 15, 2006
  • #8
btw i might of touched the dizzy while doing this but i had the ground on the battery cable off so it should matter right? o and the car is turning over it just doesnt want to fire up!

update: it will start every so often when i randomly go and try, but it will only start once and run for a couple of seconds
 

jrichker

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Apr 16, 2006
#9
  • Apr 16, 2006
  • #9
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 the above graphic 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.
 
B

BadAndy

Founding Member
Feb 21, 2001
766
0
0
Ohio
Apr 16, 2006
#10
  • Apr 16, 2006
  • #10
look UNDER the upper intake to see if you knocked off the big vac hose, that happened to me once
 
J

jstang209

20+ Year Stangneter
Jun 3, 2004
640
2
18
Stockton 209
Apr 16, 2006
#11
  • Apr 16, 2006
  • #11
ok this is kinda wierd, but i just went around slapping things, pulling stuff off and reconnecting it and now it starts.. But idles around 1k, i dont no where i can have a vac leak at. i used sealant on the manifold, hoses arent really in bad shape. I didnt notice and bad cracks or anything. The breaks were kinda hard to. While i had it running i pulled the vac hose off the FPR and it sucked to my finger. I dont no if that is alot of vac or not bc i dont have a guage but i think ill try to go get one later.
 
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