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Old 11-22-2007, 02:31 PM   #1  
kingofqueenz
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Default Need help diagnosing an on going problem

I have a 2004 mustang gt with 48k miles....im having a few problems and im not sure whats going on......Im getting extremely bad gas mileage...about 120 for a tank.....i shift at 2k so i know that driving hard is not that problem....i did an oil change about a month ago and now im really low on oil for some reason and every 2 weeks i have to put about 2 cups full of coolant to get it back to the fill line.....I also noticed at startup im getting some white smoke but im not sure if its a blown head gasket because of the fact that im getting bad gas mileage...im not sure if both problems are associated with each other....if anyone has any ideas on what this could be please let me know....i have no check engine lights, no knocking, no signs of power loss...
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Old 11-22-2007, 03:34 PM   #2  
oxfordgt
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Default RE: Need help diagnosing an on going problem

Blown head gasket. White smoke + low oil + low coolant = blown head gasket

You could be getting the bad gas mileage because of the loss of compression where the air charge is escaping thru the bad gasket.
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Old 11-22-2007, 03:56 PM   #3  
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Default RE: Need help diagnosing an on going problem

ok this makes sense...some1 on another forum said this though
"you may have an injector thats leaking or not spraying correctly. The way I check for that is to look at the fuel trims with a scan tool. If you dont have one, then you can pull the injector rail off with the injectors still connected to the rail. Then turn the key to the "on" position. NO fuel should come out of any injectors. If it does, then that injector is no good. A leaking injector will cause smoke on startup, but so will a leaking head gasket, leaking valve stem seals, (common on the 4.6l) and a host of other issues. But I am leaning more toward looking at the injectors if youre getting really ****ty gas mileage.
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Old 11-22-2007, 03:58 PM   #4  
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Default RE: Need help diagnosing an on going problem

my car has not overheated at all and runs pretty strong....any other symptoms for a blown head gasket i could look for?
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Old 11-22-2007, 04:23 PM   #5  
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Default RE: Need help diagnosing an on going problem

Drain some oil into a cup and look at it. If its milky then you got a blown headgasket. Look in the coolant overflow with the engine running at op temp if you see bubbles you have a blown head gasket.
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Old 11-22-2007, 07:13 PM   #6  
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Default RE: Need help diagnosing an on going problem

thanks, ill do that tomorrow
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Old 11-22-2007, 07:25 PM   #7  
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Default RE: Need help diagnosing an on going problem

im goin to bring the car into the mechanic tomorrow, what exactly should i say to him or have him look at it? should i tell him i think its a blown head gasket straight up? or have him run his own tests? compression test?
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Old 11-22-2007, 07:29 PM   #8  
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Default RE: Need help diagnosing an on going problem

i personally think head gasket but if he was to check for a leaking injector, he could put the fuel pressure gauge on the rail, turn the key on then off. the rail should pressurize then hold pressure, if it falls its likely a leaking injector.
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Old 11-22-2007, 07:39 PM   #9  
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Default RE: Need help diagnosing an on going problem

i hope its only that
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Old 11-23-2007, 02:08 AM   #10  
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Default RE: Need help diagnosing an on going problem

If you take off the fuel rail with the injectors still in it and turn on the key, it willleak alright,all 4 injectors are gonna fly across the room because theres nothing to hold them in place, so lets not try that one, good luck.
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