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Car wont start after MAF swap...

  • Thread starter Thread starter Black-Fifty
  • Start date Start date Dec 16, 2005

Black-Fifty

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Dec 7, 2005
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Dec 16, 2005
#1
  • Dec 16, 2005
  • #1
My car still isnt starting, it cranks over and starts but then quickly backfires and dies.
I try pulling the Maf meter plug out and it runs but just barely and back fires and sputters, then when I plug it back in it shuts off. What am I doing wrong.

I want to make sure im running the wires right. When your looking at th harness to look at the numbers do you look at it like

This:

Or this:
 

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1

1SLO306

My 97 GTP owns you ALL!
Mar 31, 2005
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17
Muhlenberg, ky
Dec 16, 2005
#2
  • Dec 16, 2005
  • #2
Shouldnt the car shut off if u pull the maf plug out???
 

jrichker

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#3
  • Dec 16, 2005
  • #3
See http://fordfuelinjection.com/index.php?p=74


This is the view from the computer side
 

Black-Fifty

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Dec 7, 2005
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Dec 16, 2005
#4
  • Dec 16, 2005
  • #4
Yeah thats what I dont understand. Any ideas?
 

Black-Fifty

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Dec 7, 2005
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Dec 16, 2005
#5
  • Dec 16, 2005
  • #5
Cool, I was doing it right, but I dont understand why it isnt starting. Maybe its a bad computer, im running the
A9S computer ima try the A9P and see if that works.
 
1

1SLO306

My 97 GTP owns you ALL!
Mar 31, 2005
904
1
17
Muhlenberg, ky
Dec 16, 2005
#6
  • Dec 16, 2005
  • #6
Black-Fifty said:
Yeah thats what I dont understand. Any ideas?
Click to expand...

here a diagram for ya. with ever wire u need to go it. hope this helps!!!
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif
 

Black-Fifty

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Dec 7, 2005
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Dec 16, 2005
#7
  • Dec 16, 2005
  • #7
I looked at all my wires and they all seem fine. Im thinking it maybe the computer, ima switch to a A9L. And see how that goes.
 

Black-Fifty

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Dec 7, 2005
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Dec 17, 2005
#8
  • Dec 17, 2005
  • #8
I switched to the A9P comuter and im still getting the same result. I dont know what else to do, Im going to recheck all my line tomarrow.
 
S

ss93cobra

Founding Member
Apr 10, 2002
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Wilmington NC
Dec 17, 2005
#9
  • Dec 17, 2005
  • #9
You hooked up the vss wires and fuel pump monitor wiring as well?
 
P

PRO50SC

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Dec 28, 2003
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Dec 17, 2005
#10
  • Dec 17, 2005
  • #10
Where are you guys getting these diagrams from?
 
S

ss93cobra

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Apr 10, 2002
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Wilmington NC
Dec 17, 2005
#11
  • Dec 17, 2005
  • #11
www.veryuseful.com
:SNSign:
 

jrichker

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Dec 17, 2005
#12
  • Dec 17, 2005
  • #12
PRO50SC said:
Where are you guys getting these diagrams from?
Click to expand...
See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-90 wiring and lots more…

http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif

Also see http://fordfuelinjection.com/ for connector printouts & other stuff.
 

jrichker

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#13
  • Dec 17, 2005
  • #13
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. There is a separate blue fuse link for the coil which can open up and rob the coil of power.
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/articles/electronics/eec-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.

In your case, check the fuel pressure immediately after the engine sputters & dies

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.
 

Paul Perreca

New Member
Mar 30, 2005
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0
Dec 17, 2005
#14
  • Dec 17, 2005
  • #14
jrichker said:
See http://fordfuelinjection.com/index.php?p=74


This is the view from the computer side
Click to expand...

Damnit Jrichker, why didn't u post that when i was doing my swap! lol I had to freakin count the holes until i got to the right one, and i kept second guessing myself, it took me forever to find the ones i needed lol
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
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234
Dublin GA
Dec 17, 2005
#15
  • Dec 17, 2005
  • #15
Paul Perreca said:
Damnit Jrichker, why didn't u post that when i was doing my swap! lol I had to freakin count the holes until i got to the right one, and i kept second guessing myself, it took me forever to find the ones i needed lol
Click to expand...
I keep surfing all these great sites a little at a time. I find new stuff and then try to remember where I found it!
 

Paul Perreca

New Member
Mar 30, 2005
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#16
  • Dec 17, 2005
  • #16
it really sucked counting pinholes lol oh well it runs!
 
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