Random Starting

Blackstang01GT

New Member
Mar 10, 2010
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I have an 01GT that fails to start sometimes. It always has pently of cranking power. Motor turns over always but sometimes will not start. Normally when the car starts, the only gauge to move is the tach which moves when the motor starts. When the car won't start, as soon as you turn the key to start both the speedo and tach peg out then fall back, all the while the motor is turning over plenty fast but no start. We think we can smell fuel so I don't think it is a fuel issue. The only problem previous was the IAC which I replaced a few days ago. If it is a PATS problem, would the motor still turn over? It appears from the book that the clutch switch has something to do with the PATS. Even though the motor will only turn over with the clutch pushed in, could the part in the switch that interacts with the PATS be going bad? Maybe an intermitent PCM?
 
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check battery. power removed!

96-98 PATS disables the starter resulting in NO-CRANK.

99-04 PATS disables fuel/spark resulting in crank with NO-START.

What is the theft light doing?

The fact that the cluster guage sweeps indicates that power was removed. Start first by checking the battery and battery terminals. Are the clean and tight? What is the condition of the battery cables? Are the grounds clean and tight?

Possible that power is being interrupted to the PCM which is causing the PCM to re-learn all idle/fuel trim values.

Bottom line, expect problems if there are any problems with the battery and charging systems.

The safety interlock on the clutch has nothing to do with your problem. Failing to push in the clutch simply interrupts power to the start solenoid.

Also try cracking the throttle half way open. If this improves starting, suspect bad IAC.
 
Sounds like PATS could be my problem. Theft light appears normal. I was taking the battery cables off each time I was messing with the clutch switch, could that be the reason for the gauges sweeping? Also the IAC has been acting up for years. I would take it off and do the carb clearner trick which would work for up to a year with no problems. When starting issue came up I put a new IAC on thinking that might be a cause. Same problem after new IAC. I also bought a new ignition switch. The car was starting OK but decided to put the switch on anyway. Must not of had it installed right because after the install, same problem, crank but no start. Put the old switch back on, car started.

I only have one key so if PATS is my problem, I should take it to a dealer, buy two keys, and have the PCM reprogramed? Is that the normal PATS problem, crank but no start. I also read about the theft light doing crazy things.
 
key cycle to re-pressurize fuel system

Your response is confusing. Theft light appears "normal" but suspect a PATS problem. What's up with that?

The theft light will flash in a predictable pattern depending upon the particular error.

Further, you state that fuel can be smelled. If Theft (PATS) has been tripped, the fuel is disabled. NO FUEL, no fuel smell.

If you are disconnecting the battery cables, then it is expected operation for the guages to sweep on the next start.

How normal PATS (Theft) reacts by MY has already been given. IDK, maybe your Mustang is "special" (or has an aftermarket alarm installed).

So if the problem is no-crank, for an 2001, it can not be the theft (PATS) causing it.

It is normal for the motor to crank only when the clutch is depressed. That is the clutch safety interlock. All manual Mustangs do it. In concept is the same as the automatic transmission interlock that disables the starter if not in park or neutral. It has nothing to do with PATS.

Remember if you disconnect the battery, it is normal for the car to run poorly until the fuel idle trim values are re-learned.

Fuel pressure leak down can cause hard starts. Trying cycling on/off the key several times (do not start). You should hear the fuel pump run for a few seconds each time. If this improves the starting, suspect fuel pressure leak down (leaky fuel injector, bad fuel pump check valve, or bad damper).

Does cracking the throttle half way open improve the hard start?
 
I recently had an issue with my needles pegging when starting. First check your terminals are as tight as can be. Secondly, how old is the battery? When the original battery in my car was on its way out everytime I started the car the needles would peg, until one day it didnt have enough juice to start and needed to be replaced.

Start cheap and free with the repairs.

Good Luck!