Won't Start After Being Stored

gotchopsticks

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Sep 4, 2004
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Hello, I'll start off by confirming that I have searched the threads and followed the guidance in the other posts about this problem to no avail, so here I am. 2002 GT 106,000 miles, no problems before storing and replaced plugs about 4,000 miles ago, but I did neglect to put fuel stabilizer in (I did't plan to store it for long but go deployed before I could take further measures). Anyways, it was stored with maybe a gallon of fuel for about 2 years, battery connected to a battery saver (Genesis G750). Outline of events below:

9 June 2017- connected battery, primed several times, attempted to start - no start
10 June 2017 - added 2 gallons of 91 octane, confirmed full battery charge, attempted to start - ran for several minutes but exhaust smelled very bad, rough idle, hesitation to increase RPM's. Shut off for 5 min, attempted to start - no start
24 June 2017 - attempted to start after priming several times - no start. Let it sit with ignition "ON" for several minutes - started and ran for 5 min and ran great, no bad smell no hesitation. Pressed Schrader valve before cranking - no fuel expelled; pressed Schrader valve while running - no fuel expelled
24 June 2017 - put in 5 gallons of 91 octane, Lucas fuel treatment, new oil & filter, replaced flimsy PCV hose that was collapsing on itself - attempted to start - no start. Tried repeating the steps that seemed to work before changing the oil and could not get it to start again; attempted start at least 10 times.

Items checked:
-PATS not triggered: THEFT light does not blink while cranking; tried lock & unlock with remote - no change
-Odometer blank while cranking
-Fuel pump hums when ignition turned to "ON"
-Battery full charge
-With ignition on, pressed Schreder valve - no fuel (also no fuel expelled when pressed while running)
-Removed Diablo Tune - no change
-Confirmed all fuses operational
-No trouble codes present
-Used rubber mallet to hit fuel tank while cranking - no change

Items not checked:
-Have not pulled injectors or plugs to confirm fuel or ignition - it ran several times so I didn't think that was a high likelihood
-Have not checked fuel rail pressure with external gauge - Predator Diablo turner read "75% FP" but "0psi FRP" with ignition "ON"

I've attached a spreadsheet of the other readouts from the Diablo, not sure if that will help diagnose the issue. Thanks in advance for any guidance.
 

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The fact there's no fuel at the fuel rail is a huge symptom. I'm assuming that you never hear the fuel pump run during any of the key cycles.

The next test should be to CONFIRM there is key on power at the trunk mounted IFS switch. Use a known good ground.

If there is power at the IFS switch then:
  • possible bad fuel pump
  • possible bad FPDM (less likely)
  • possible bad PCM (less likely)
IF there is no key on power at the trunk mounted IFS switch then a CCRM issue is possible but more tests will be needed to confirm.

IMO the odds favor a bad fuel pump especially if power has been confirmed and confirmed zero fuel pressure.

1996+ Crank with no start check list:
http://www.allfordmustangs.com/forums/4-6l-tech/336452-1997-mustang-wont-ignite.html#2984838
 
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wmburns, thanks for the reply. I agree, but I find it odd that would run fine (if i got it started) even though there was no fuel expelled when pressing the Schrader valve. I do hear a hum/buzz for 3-4 seconds when I turn the key on, I'm assuming that is the fuel pump. The trunk mounted IFS switch is aka the inertia switch, correct?
 
If you HEAR the fuel pump run at initial key on, THEN there must be power at the fuel pump.

It's not possible for a motor to run with no fuel. There fore there's something else going on. I have heard of cases where the Schrader valve sticks internally and won't open. The valve is the same as what is used on most every car tire on the road. It is easily serviceable. Just remove the core with the same tool used to remove the core in tires.

I am also aware of cases where the fuel pump is so weak that it's able to run the motor at idle but not anything above an idle.

Seems like we should fix the Schrader valve so that at least we aren't going on a trouble shooting wild goose chase.

Once we know for certain there is fuel pressure the trouble shooting can focus on other possible causes for a crank with no start.

Hint: pay attention to anything that affects the MAF. For example a vacuum leak. For a quick trouble shooting test try disconnecting the MAF.

Also note that the fuel rail pressure sensor (FRPS) is also a no start sensor. Check the intake vacuum reference line is connected and leak free. Inspect for raw gas.

If all else fails. Start over. Follow the check list. Don't "assume" anything. Recheck everything.
 
Last edited:
Understood. So next steps are going to be:
-Service Schrader valve and connect fuel pressure gauge to confirm fuel rail pressure
-Pending outcome of Schrader valve service, confirm fuel pump is operational & test FRP sensor
-Check all vacuum hoses & try disconnecting the MAF
-Confirm spark

Thanks again for the guidance.
 
Update:
So the issue was the fuel pump. However, there was still some strange activity I'd like to share for anyone else seeing this problem. Before replacing the fuel pump, I serviced the Schrader valve with no change. Just for diagnostic purposes, I attempted to start the car with the valve removed (the entire thing, not just the valve stem). Oddly enough, it started on the first try. It idled fine and I was able to rev 3k rpm just fine. It started idling rough after several minutes and I shut it off. At that point I had enough of the trouble shooting and replaced the fuel pump. It started up first try after completing the install and priming it several times. Runs great now. Thanks again for the guidance!