Fuel pump?

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/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

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.

4.) Spark & fuel 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.

The relay is under the driver's seat.

Fuel pump, relay, fuse, ignition switch, wiring. Not necessarily in that order. If none of that jumps out at you then I'd get a fuel pressure pressure guage to confirm or rule out a pump or pump system problem. If that checks out... I'd go through jrickter's checklist (you can find it repeatedly posted on many threads) and diagnose the problem that way.

RsStanG1987 said:

Where is the fuse?

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the fuel pump uses a fusible link, not a fuse. the link is off the solenoid.

you cant beat JR's list for a complete and organized listing of what to check. im with Daggar on what to do - ill add to it.

assuming you are right about no pump priming: were it me, i would pull the FP relay. whip out the DMM and check the values. make sure you have the coil triggers (if missing positive coil, check the inertia switch in the trunk). puter sends ground. then the solenoid fed wiring goes to the common terminal. then output.

go from there. good luck.

Just went thru similiar issues with my 95, took me months to figure out the problem, when you turn the key on you should hear the pump prime, if not I would grab like a pin or something, that little thing on the fuel rail that looks like a valve stem, push down on the pin inside and fuel should squirt out, then you will know if fuel is getting to the fuel rail.

RsStanG1987 said:

I checked the fuse the inertia switch and changed the relay so. So does that mean the fuel pump is bad??? Do they just go bad out of nowhere?

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what did you find when you checked each terminal in the FP relay socket? that will tell you what direction to go. this will also tell you if it is the pump. one can jump the self test connector to make the pump run (for diagnostic purposes). JR listed a link to it in his post.

as opposed to depressing the schrader valve on the fuel rail, get yourself a FP gauge - be it a permanent gauge or a diagnostic gauge. see what (if any) pressure you have. if you have too little pressure, get back to us (testing info to determine whether it is pump related or FPR related can be given).

good luck.

RsStanG1987 said:

It was the fuel pum somebody told me to have someone hold turn the key as if i were turing the car over and hit the tank with a rubber mallet and see if it primes. sure enugh it did. I got a new pump and the car runs great. Thanks for the help

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well that is one way to check it (i might have simply confirmed that the pump was getting power from the relay socket and/or at the pump or run it from the self test connector). but the RUBBER hammer method always works.

glad to hear it is good to go.