Crank but no start-- please help

1991notchbackLX

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Dec 25, 2007
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I did a search on this topic, but all I got was more confused. My 1999 GT has been sitting for a few weeks. I started it about a week ago and it cranked for a while before starting but eventually started up after about 30 seconds. I went out to start the car today to go for a drive because it was beautiful outside, and it just cranks with no start. The car is parked on an incline, so I thought perhaps all of the fuel drained back to the tank and out of the lines. I also thought it could somehow be out of gas. I put a few gallons of gas in it and it still wont start, it only cranks. Let the car rest for 15 minutes and tried it again and it still only cranks without starting. I've read that it could be the PATS system or fuel pump? Please help me troubleshoot this. Thanks in advance!

Chris
 
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wmburns

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Aug 14, 2009
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Check for vacuum leaks. Clean the MAF. Use only a product designed for the job. No brake clean. No carb/choke cleaner.

Turn the key to run (do not crank). Confirm that the theft light goes out after a 3 second "prove out". Confirm that the theft light does not blink during cranking.

Next cycle the key off/on/pause (do not crank) several times. LISTEN for the fuel pump to prime each time. Do you hear the FP run? Does this improve starting? If so, suspect a fuel pressure leak down or a bad fuel pump.

Also, on a FI car, parking on an incline will NOT make a difference. Why? Because the lines are supposed to remain presurized while the car is off. Parking on an incline could make re-pressurizing the system more difficult if the fuel pump pick up has been uncovered. But a small amount of fuel is supposed to remain in the fuel pump basket. So unless you have modified the basket by drilling holes, there should be enough fuel in the basket for the car to start.

Next, hold the throttle half way open during cranking. Does this improve starting? If so, suspect a bad IAC.

Last, disconnect the MAF. Does this improve starting?

If asked to guess, I lean towards fuel pressure leak down from the fuel injectors, fuel pressure sensor, damper, or bad fuel pump check valve. Note, the check value is serviced with the fuel pump itself.
 

wmburns

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Aug 14, 2009
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The 96-98 MY PATS disables the starter. This give a no crank symptom.
The 99-04 MY PATS disable fuel and spark. This gives a crank with no start symptom.

The blinking PATS light means that the anti-theft system has been activated.

First try resetting by unlocking the driver's door or using the remote FOB.

Also removed everything from the key and try with just the key. Sometimes metal objects can interfere with the PATS signal.

Do you have a spare key to try? You are aware that the key does have to be programmed before use?

For some MY's, the light will display a blink code. Also research on how to active the cluster diagnostic mode.

Review the following information esp post #10.
http://www.stangnet.com/mustang-forums/825922-96-gt-theft-pcm-question.html

http://www.stangnet.com/images/stories/docs/sn95_TSBs/01-06-02.pdf
 

1991notchbackLX

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Dec 25, 2007
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I tried using a spare key as well as removing all objects from the key chains. The theft light blinks before the key is inserted into the ignition, but does go off after the three second "prove out." The car does not start with the throttle at half, and it does not start with the MAF unplugged. I DO NOT hear the fuel pump priming at all. I believe I have a bad fuel pump, but I'm still weary of the PATS system.

What do you suggest I try next?
 

wmburns

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How to test fuel pump 96-04 MY

If the theft light goes out after the 3 second "prove out" and it does NOT come on during cranking, this is NOT a PATS problem.

If you want further proof this isn't a PATS problem, test for spark. Or spray a small amount of starting fluid in the intake throttle body and see if it "hits".

Assuming that you have checked all of the fuses in the engine bay and driver's kick panel, review the following thread. It contains DETAILED information on how to confirm the diagnosis of a bad fuel pump on a 99-04 MY.

http://www.stangnet.com/mustang-forums/824672-fuel-delivery-issues.html
 

1991notchbackLX

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Dec 25, 2007
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The fuses checked out inside and in the engine bay. The inertia switch is not tripped. The "THEFT" light now comes on solidly during cranking. How do I go about resetting the PATS system? Can I disable it all together? Thanks for the help. This is a terribly frustrating problem and I have literally like 15 minutes a day to troubleshoot and try things between jobs.
 

wmburns

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Aug 14, 2009
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How to troubleshoot PATS 99-04 MY

Try reseting with the key FOB or by unlocking the driver's door.

Take everything off of the key ring and try with just the key.

The links have instructions on how to access the cluster diagnostic mode. Post the codes and descriptions.

As to how to bypass, dealer, locksmith, or hand held tuner.

Check out
http://www.stangnet.com/images/stories/docs/sn95_TSBs/01-06-02.pdf

01 Bullitt PATS Problem - Ford Mustang Forums

Cluster diagnostics:
http://www.mustangworld.com/ourpics/fcar/dtcodes.htm
 

Dust

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Jan 13, 2022
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In case anyone was wondering if these old forum posts still help they do. Got my 96 mustang running after looking through this forum. The car is older than i am so i appreciate it
 
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