another cranks but wont start(no fuel)

mob

the guy who hits on his mom
15 Year Member
Oct 3, 2003
2,497
93
79
31
Dallas, TX
Hey guys ive read jrichkers write up many times and dosent help. I moved my selinoid inside my fender. Hooked everything back up and cranks but no start. Turns out the fuel pump isnt priming. Ive tried using a volt meter, and i put it on the yellow part of the fusable link and it read about, .3 Then i put it on the black parts, and it got about .1-.3 But I changed the ground from the chasis to the engine for the meter and it went to 12.46 volts on each of the 3 wires in the fusable link. Every diagram ive seen has the fuel pump relay under the drivers seat, i have nothing under there.

The car is a 1993 5.0.
 
  • Sponsors(?)


HISSIN50

"How long does it take to get help in here?
SN Certified Technician
Nov 29, 1999
31,179
28
129
Your fuel pump relay should be near the pass. strut tower, next to the WOT relay.
 

LX93RiceKill

New Member
Jul 9, 2006
14
0
0
Is it not getting fuel at all, or just when you're trying to start it? Spray a bit o starter fluid or gas into the throttle body, and crank it up. See if it shuts off, or if it keeps running.
 

mob

the guy who hits on his mom
15 Year Member
Oct 3, 2003
2,497
93
79
31
Dallas, TX
i doubt its getting fuel at all because the fuel pump dosent make one sound, it just cranks and keeps cranking at like 1500 rpm but never starts, and hissin what does it look like? is it under the maf? idk what the wot relay is either. Thanks guys.
 

jrichker

StangNet's favorite TOOL
SN Certified Technician
Mar 10, 2000
27,357
2,824
234
74
Dublin GA
lowendmac.com
Here's the later model test path - the wire colors are different.

Fuel Pump Troubleshooting for 91-93 Mustangs

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.

If the fuse links 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. A tire pressure gauge can also be
used if you have one - look for 37-40 PSI. Beware of fire hazard when you do this.


No fuel pressure, possible failed items in order of their probability:
A.) Tripped inertia switch – press reset button on the inertia switch. The 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.

The electrical circuit for the fuel pump has two paths, a control path and a power
path.

The control path consists of the computer, and the fuel pump relay coil. It turns
the fuel pump relay on or off under computer control. The switched power (red
wire) from the ECC relay goes to the relay coil and then from the relay coil to the
computer (light blue\orange wire). The computer provides the ground path to
complete the circuit. This ground causes the relay coil to energize and close the
contacts for the power path. Keep in mind that you can have voltage to all the
right places, but the computer must provide a ground. If there is no ground, the
relay will not close the power contacts.

The power path picks up from a fuse link near the starter relay. Fuse links are like
fuses, except they are pieces of wire and are made right into the wiring harness.
The feed wire from the fuse link (pink/black wire) goes to the fuel pump relay
contacts. When the contacts close because the relay energizes, the power flows
through the pink/black wire to the contacts and through the dark green\yellow
wire to the inertia switch. The other side of the inertia switch with the
brown\pink wire joins the pink/black wire that connects to the fuel pump. The fuel
pump has a black wire that supplies the ground to complete the circuit.

Remember that the computer does not source any power to actuators, relays
or injectors, but provides the ground necessary to complete the circuit. That
means one side of the circuit will always be hot, and the other side will go to
ground or below 1 volt as the computer switches on that circuit.



diagram of the wiring for 91-93 cars.

Power circuits:
Power feed: Look for 12 volts at the pink/black wire (power source for fuel pump relay).
No voltage or low voltage, bad fuse link, bad wiring, or connections. Remember that on 92
or later models the fuel pump relay is located under the Mass Air meter. Watch out for the
WOT A/C control relay on these cars, as it is located in the same place and can easily be
mistaken for the fuel pump relay.

Relay: Turn on the key and jumper the ECC test connector as previously described. Look
for 12 volts at the dark green\yellow wire (relay controlled power for the fuel pump). No
voltage there means that the relay has failed, or there is a broken wire in the relay control circuit.

Inertia switch: Check the brown/pink wire, it should have 12 volts. No 12 volts there, either
the inertia switch is open or has no power to it. Check both sides of the inertia switch: there
should be power on the dark green\yellow (inertia switch input) and brown/pink wire
(inertia switch output). Power on the dark green\yellow wire and not on the brown/pink wire
means the inertia switch is open. Press on the red plunger to reset it to the closed position.
Sometimes the inertia switch will be intermittent or will not pass full power. Be sure that
there is 12 volts on both sides of the switch with the pump running and that the voltage drop
measured across the switch is less than .75 volts.

Control circuits:

Relay: The red wire for the fuel pump relay coil gets its power feed from the ECC relay.
No 12 volts here, and the ECC relay has failed or there is bad wiring or bad connections
coming from it. The ECC relay is located on top of the computer, which is under the passenger’s
side kick panel. It is not easy to get to, you must have small hands or pull the passenger side
dash speaker out to access it.

Relay: The light blue/orange wire provides a ground path for the relay power. With the test
connector jumpered according to the previous instructions, there should be less than .75 volts.
Use a test lamp with one side connected to battery power and the other side to the light blue/orange
wire on the fuel pump relay. The test light should glow brightly. No glow and you have a broken
wire or bad connection between the test connector and the relay. To test the wiring from the
computer, remove the passenger side kick panel and disconnect the computer connector.
It has a 10 MM bolt that holds it in place. Remove the test jumper from the ECC test connector.
With the test lamp connected to power, jumper pin 22 to ground and the test lamp should glow.
No glow and the wiring between the computer and the fuel pump relay is bad.

Computer: If you got this far and everything else checked out good, the computer is suspect .
Remove the test jumper from the ECC test connector located under the hood . Remove the
plastic cover over the computer wiring, but leave the computer wiring connector plugged
into the computer. With the ignition switch in the run position, connect a test lamp to the
battery and back probe pin 22, the light blue/orange wire with it. The lamp should glow
brightly. No glow and the computer has died a sad death. :( If you used a voltmeter instead
of a test lamp, you should see battery voltage, whatever that may be…

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/

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

Fuel pump runs continuously: The light blue/orange wire has shorted to ground. Disconnect
the computer and use an ohmmeter to check out the resistance between the light blue/orange
wire and ground. You should see more than 10 K Ohms (10,000 ohms) or an infinite open
circuit. Be sure that the test connector isn’t jumpered to ground.
 

mob

the guy who hits on his mom
15 Year Member
Oct 3, 2003
2,497
93
79
31
Dallas, TX
thats a great right up and all but still dosent help me. I dont know what diagrams apply to my car, i know the one that says the fp relay is under the driver seat is useless to me. Once I do find the relay under the maf, and I test it, and if the volts arent accurate then whats wrong with it? could it be shorted? where would i even start to fix it from.

And if the volts are accurate, then whats wrong with it? Im so screwed I havent had a car for 2 days.

and can someone tell me what this wire I circled is for? I dont remember grounding this when i put the selinoid back together, if I accidentally put this on the selinoid could that be bad? Could it have anything to do with the fuel pump? :bang:

circle22ht.jpg
 

Attachments

jrichker

StangNet's favorite TOOL
SN Certified Technician
Mar 10, 2000
27,357
2,824
234
74
Dublin GA
lowendmac.com
The unknown wire could be anything. If it is a black wire with a greeen stripe, it is the computer power ground. Fail to connect it and the whole computer system quist working, including the fuel pump.


The diagram shown is the correct one for your car.

Do the test path steps one at a time. Do not skip any steps. When you find something that isn't right, read the test path instructions. If that doesn't help, post your result & questions here.
 
Thread starter Similar threads Forum Replies Date
Andresquintana.mma Another Crank But Wont Start Fox 5.0 Mustang Tech 16
modulistic Another Crank No Start. SN95 4.6L Mustang Tech 11
HOOKERBEAR Yet Another Cranks But No Start Thread Fox 5.0 Mustang Tech 1
93notchback another crank, no start......... Fox 5.0 Mustang Tech 4
Bill Cool Another "cranks but no start" thread. Fox 5.0 Mustang Tech 15
cenok is family it's one thing after another...turning my crank Fox 5.0 Mustang Tech 3
darkhorse1 Another crank question SVT Tech Forum 2
S Another Idle surge post with microsquirt Digital Self-tuning Forum 2
Andresquintana.mma Engine Another bad distributor? Fox 5.0 Mustang Tech 38
S Another addition to the fleet The Welcome Wagon 5
MrFoxNutCase Progress Thread Another notchback... 88 OE project 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 7
R Progress Thread Just another 93 convertible project 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 11
Anti_Hero0932 Another pony in the stable 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 15
T Please help, a noob needs help with another exhaust question! 2005 - 2014 S-197 Mustang -General/Talk- 5
D Another Newbie here! The Welcome Wagon 8
LILCBRA Another stumbled upon article 1974 - 1978 Mustang II Talk & Tech 15
A Yet Another Cracked Aqua Dashpad Owner Searching For a Solution 1965 - 1973 Classic Mustangs -General/Talk- 0
M Another newbie. The Welcome Wagon 5
C Another newbie. , again. The Welcome Wagon 10
horse sence You guessed it ,another 67 FB. Conversion Classic Mustang Specific Tech 105
silverlx50 Engine Can yall help me add another 100HP? Fox 5.0 Mustang Tech 19
G Another NSG thread 93/AOD with a C4 NSS Fox 5.0 Mustang Tech 0
S Electrical Oh no not another 88’ turn signal thread! Fox 5.0 Mustang Tech 6
Justin87 Engine Yet another explorer intake valve cover question Fox 5.0 Mustang Tech 10
evintho Brakes Another dumb 5-lug swap question. Fox 5.0 Mustang Tech 1
joetrainer31 Progress Thread Got Another One! Pics Fox 5.0 Mustang Tech 90
B Engine Another Poor Idle/Running Rich Thread Fox 5.0 Mustang Tech 8
twogts4us Drivetrain Is it another bad throw out bearing? SN95 4.6L Mustang Tech 0
G Engine Another 393 stroker thread Classic Mustang Specific Tech 0
ChillPhatCat Progress Thread Haven't posted in a looong time... rescuing another 'stang... '89 Vert 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 20
J I want another fox 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 8
L Another rubbing thread - 88 GT Vert lowered with 235/55 x17s 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 14
GaryM Another Newbie The Welcome Wagon 1
killer5.0 Need to move my car to another shop mid mini-tub process....how to transport 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 14
MustangHunter5.0 Hello, another mustang owner here.. The Welcome Wagon 2
T Another newbie The Welcome Wagon 2
D Another newbie to Stangnet in Corona, CA - '88 The Welcome Wagon 7
9 SN95 Another 5.Slow from Alberta, Canada 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 11
Icemanxxxv Not Another New Guy? The Welcome Wagon 1
B '03 GT Another Intake Leak, Time for KB 2.1? 1996 - 2004 SN95 Mustang -General/Talk- 15
F another exhaust question 1965 - 1973 Classic Mustangs -General/Talk- 10
F another exhaust question The Welcome Wagon 1
H Another windstar swap. 1996 - 2004 SN95 Mustang -General/Talk- 0
Woody3882 Another Newbie The Welcome Wagon 1
C Another Newbie The Welcome Wagon 2
A Another one Bites the Dust. RIP Project Eleanor:( 2015+ (S550) Mustang -General/Talk 7
A Fox Another Fox Leaning.. 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 5
D Another new guy... (and seeking advice) 1965 - 1973 Classic Mustangs -General/Talk- 15
horse sence Build Thread Another 68 coupe to fast back conversion Classic Mustang Specific Tech 84
Reddevil91 Ok I’m back with another possible, this time Injectors! 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- 8
Similar threads