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Sometimes car won't start

7K views 20 replies 6 participants last post by  Mercedez L. 
#1 ·
It is getting spark (Battery very strong) but not sure if it is getting air or fuel.
It is like it won't turn over. I have to keep cranking engine over before it starts.
The symptom is the same as when PCV valve was disconnected and car would not start.

Any ideas what problem could be?:nonono::facepalm:
 
#5 ·
I would run the codes to get an idea first off.
 
#13 · (Edited)
(Engine Wont Start Regardless Of How Long You Crank It)

The best place to start for the above condition is to figure out what element youre missing (fuel,spark,compression)??? Youre missing one or more of these elements.
Do the test below to try & reveal the missing element.

1) Remove the small,black breather tube from the throttle body port (tube runs between the tb & the oil filler neck on the passenger valve cover)
2) Spray starting fluid or carb cleaner into the tb port (where you removed the tube from)
3) Reinstall the tube & try starting the car
4) If the engine starts & runs for a few seconds then dies,youve got a No Fuel issue (i.e.- No/Low Fuel Pressure or Injectors Not Pulsing)
5) If the engine doesn't start at all,youve got a No Spark issue


(Engine Starts After Long Crank Times)

The condition above is usually fuel related,unless it only occurs during a Hot Restart.
The next time you attempt a startup & it doesnt start immediately,try this:

1) Press the gas pedal to the floor & hold it there while you turn the key and try to start it.If it starts,this indicates you're getting too much fuel.When you crank the engine while flooring the pedal,it causes the ecm to shut the injectors off to clear an engine flood condition.
Possible causes=
leaking fuel pressure regulator,regulator stuck closed,leaking fuel injector.One way to check the regulator is to turn the key on/engine off,remove the vacuum hose from the regulator and see if it has fuel inside of it & make sure no fuel is seeping from the regulator vacuum port.If either condition is present,the regulator is bad.
2) If that didnt work,cycle the key on/off 5-6 times then try to start it.
If it starts,that indicates the fuel filter may be partially clogged or the fuel pump is bad.Cycling the key on/off builds fuel pressure up in the fuel rail,allowing the engine to start.
3) Test fuel pressure at the Schrader valve on the fuel rail using the steps below.
Attach a fuel pressure gauge to the Schrader valve,turn the key on/engine off,record fuel pressure (it should be 30-45psi) turn the key off,wait 60 seconds,record pressure again.Did pressure drop more than 5psi in that 60 second time frame??
If yes,wrap a rag around a soft section of the fuel return hose,pinch the hose closed using vice grips,turn the key on/engine off,record pressure,turn the key off,wait 60 seconds,record pressure again.Did pressure still drop more than 5psi??
If no,the fuel pressure regulator is bad.
If yes,a injector is leaking or the fuel pump is bad.Sometimes when an injector is leaking,the spark plug will be wet with fuel.

(Wont Start When Hot)

The condition above is usually caused by a defective fuel pressure regulator,pip sensor (inside distributer) tfi module,coil.
Try removing the spout plug (tied into the tfi wiring harness) then attempt a startup.If it starts without the spout plugged in,that indicates the pip sensor is bad.The fpr,tfi & pip sensors are notorious for causing no starts & hard starts once the engine gets hot.They get heat soaked & begin malfunctioning.
A bad capacitor on the ecm board & a defective ignition switch can also cause no starts & hard starts.
 
#14 ·
(Engine Wont Start Regardless Of How Long You Crank It)

The best place to start for the above condition is to figure out what element youre missing (fuel,spark,compression)??? Youre missing one or more of these elements.
Do the test below to try & reveal the missing element.

1) Remove the small,black breather tube from the throttle body port (tube runs between the tb & the oil filler neck on the passenger valve cover)
2) Spray starting fluid or carb cleaner into the tb port (where you removed the tube from)
3) Reinstall the tube & try starting the car
4) If the engine starts & runs for a few seconds then dies,youve got a No Fuel issue (i.e.- No/Low Fuel Pressure or Injectors Not Pulsing)
5) If the engine doesn't start at all,youve got a No Spark issue


(Engine Starts After Long Crank Times)

The condition above is usually fuel related,unless it only occurs during a Hot Restart.
The next time you attempt a startup & it doesnt start immediately,try this:

1) Press the gas pedal to the floor & hold it there while you turn the key and try to start it.If it starts,this indicates you're getting too much fuel.When you crank the engine while flooring the pedal,it causes the ecm to shut the injectors off to clear an engine flood condition.
Possible causes=
leaking fuel pressure regulator,regulator stuck closed,leaking fuel injector.One way to check the regulator is to turn the key on/engine off,remove the vacuum hose from the regulator and see if it has fuel inside of it & make sure no fuel is seeping from the regulator vacuum port.If either condition is present,the regulator is bad.
2) If that didnt work,cycle the key on/off 5-6 times then try to start it.
If it starts,that indicates the fuel filter may be partially clogged or the fuel pump is bad.
3) Test fuel pressure at the Schrader valve on the fuel rail using the steps below.
Turn the key on/engine off,record fuel pressure (it should be 30-45psi) turn the key off,wait 60 seconds,record pressure again.Did pressure drop more than 5psi in that 60 second time frame??
If yes,wrap a rag around a soft section of the fuel return hose,pinch the hose closed using vice grips,turn the key on/engine off,record pressure,turn the key off,wait 60 seconds,record pressure again.Did pressure still drop more than 5psi??
If no,the fuel pressure regulator is bad.
If yes,a injector is leaking or the fuel pump is bad.

(Wont Start When Hot)

The condition above is usually caused by a defective fuel pressure regulator,pip sensor (inside distributer) tfi module,coil.
Try removing the spout plug (tied into the tfi wiring harness) then attempt a startup.If it starts,that indicates the pip sensor is bad.The fpr,tfi & pip sensors are notorious for causing no starts & hard starts once the engine gets hot.They get heat soaked & begin malfunctioning.
A bad capacitor on the ecm board can also cause no starts & hard starts.
Wow! thanks that is ALOT of info:cool:
 
#18 ·
Come on Mercedez we know you can do it.

I have a girlfriend of mine who used to be very prissy and now just bought a Jeep and it seems like I am helping her all the time working on but she is also learning which is awesome.

I have faith in you.
 
#20 ·
It is getting spark (Battery very strong) but not sure if it is getting air or fuel.

It is like it won't turn over. I have to keep cranking engine over before it starts.

The symptom is the same as when PCV valve was disconnected and car would not start.



Any ideas what problem could be?:nonono::facepalm:

I had a similar issue like this back in the day when I had Fox body mustangs. At times it was the fuel pump that went bad but there was once that it was some type of relay that was under the driver seat. I'm pretty sure this relay was related to the pump. When I'd turn the key, as I held the relay, I could feel like a rapid ticking sensation from within the relay. I changed it and the car started just fine. It was like a $5 fix. Not sure if that relay is in all Fox bodies or just the one I had.


Sent from my iPhone using Mustang Evolution
 
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