Tony stang

Hey guys new member here and pls forgive me in advance if I posted in the wrong forum. Love all u guys for the great info u all post to help others with their technical issues.. I have one and maybe u guys can help. I have a 08 GT with just ur basic bolt ons..CAI .. Bama tuner .. Under drive pulley exhuast from the cat backs with 373 rears.. My problem is this .. And it just started happening. On a cold start the stang starts up fine ..runs good no issues .. But once I shut it off.. She cranks but doesn't start.. I have to wait till she cools off a bit and when she does .. She comes right back on.. No CEL .. Nothing .. And it's racking my brain. Something is over heating and I don't know what it is . I even hear the fuel pump coming on.. But nothing when she's hot. Maybe the fuel pump relay? I don't know.. Any advice would be greatly appreciated .

m05fastbackGT

From what you just described, it's either the fuel pump going bad or fuel relay as you mentioned.. Therefore I would start with the relay first and also have the fuel pump checked as well.. But it's definitely not the alternator, otherwise it wouldn't have enough cranking power for starting your car regardless of how cold or hot the engine may happen to be, as that wouldn't be a factor.. I would also recommend having your fuel injectors checked as well just to be on the safe side..

05YellowGT

Check your battery too, mine was going bad and when I stopped for a short time while and the engine was hot, it wouldn't start. The battery would heat soak and since it was weak it wouldn't start till it cooled down.

Jazzman442

This could be caused by a few things as some have mentioned.
If it only happens when hot it could be vapor lock. Fuel line to close to the engine gets hot and it will boil and will not flow correctly. The other thing is did you check the spark? I have seen coils go bad and not work when they are hot.

Good luck those are fun to trouble shoot as the engine has to be hot.

07 Boss

Have you tried to clear the cylinders when this happens? Maybe 4-5 times in all the years I've had my car it has done this. I usually clear the cylinders and keep cranking as I return the throttle to zero and she starts right up. Don't have any explanation why this is, just my experience.

Tony stang

I swapped out the fuel pump relay and still having the same issue .. But I did realize when she's hot .. I don't hear the fuel pump priming .. But when it was raining here a few days ago .. I drove her to work .. Shut her off and guess what .. She started right up.. Maybe the rain was cooling off something underneath.. I do notice .. When I am in the car .. It's incredibly hot at times . Now mind u.. I have a GT 500 tranny in the car.. That's how I purchased it .. Not from the dealer of course . I changed he spark plugs .. And the coil packs look good .. Haven't gotten to the other stuff.. Yet.. I know it's something stupid causing the problem.. My friend said it could be the wire harness.. But I don't think so. Any more advice will be appreciated . Thanks .

m05fastbackGT

I would recommend taking your car to either a shop or local dealer and have your electrical system tested.. Until you have the system diagnosed, you're just pretty much spinning your wheels and grasping at straws not knowing exactly what's causing your car not to turn over when it's warm.. Anyway just my opinion

07 Boss

Have you tried to clear the cylinders when this happens? Maybe 4-5 times in all the years I've had my car it has done this. I usually clear the cylinders and keep cranking as I return the throttle to zero and she starts right up. Don't have any explanation why this is, just my experience.

05YellowGT

What does "clear the cylinders" mean?

07 Boss

If you hold the pedal to the floor while cranking the starter it cuts off the fuel injectors. This allows you to clear the cylinders of any fuel that may be in there. Basically helps if the engine gets flooded for some reason. I have found in my 20 or so no start scenarios when hot, that holding the pedal to the floor while cranking and then letting off back to the idle position while still cranking the motor will start her right up.

It happened yesterday with me. I stopped to get gas and the card reader wasn't working so I immediately tried to start her up to move to another pump. Cranked but wouldn't fire up. Pressed the pedal to the floor and started cranking. While continuing to hold the key in the start position I released the pedal and she fired right up. I don't know why she occasionally does this but it is only when I immediately try and restart the car when she's hot. It is a rare occurrence and happens only about 2-3 times a year.

I only mention it as it is something to try without costing any money. I suspect it may be a tune thing but it's never been much of an issue.

05YellowGT

OK, good to know ...

Glenn

autozone will test your charging system for free

stang09

09 ford mustang GT premium won't start
I checked the battery and altenator, starter cables
radio was off and dash started to flash and radio came on making noise all by itself. I haven't a clue does anyone have any ideas I just purchase this car with 57000 miles on it.

m05fastbackGT

It means that it's time to replace the battery.. Whenever your dash flashes and radio comes on by itself making noises, your battery is nearly completely discharged.. Try jump starting or use a battery charger.. If your car still doesn't start, your battery is toast..

stang09

thanks bud I got a new battery today thanks for the input

stang09

hello all I looking to get my 09 gt pipes change so it could sound a lot better so fat I have I regular stock one in it I trying to save cost any advise you could get me