On intial start she idles terrible and craps out. Greyish smoke out the exhaust and she smells like gas. We've replaced the MAF sensor already--still doing it! Now she totally craps before--before the MAF was replaced she would almost **** out but then start racing to try and correct. No it's not a blown head gasket!

a rough guess as to the excessive fuel smell and smoking < I would say that the seal under the injector tip is damaged or missing and that fuel is bypassing the injector
probably now flooded and that is why it will not start
lean codes are generally caused by a faulty HO2S sensor ( heated oxygen sensor) in the exhaust manifold/s before the cat converter/s
other possible causes are MAF/VAF sensor faults and low fuel pressures

If it is the v8, the most common cause for greyish, white smoke is bad valve stem seals. True white smoke smells very sweet and is caused from coolant being buring in the combustion chamber.

Fuel pressure regulator bad. Vacuum operated , pull the vacuum line. Smells like fuel. It's bad .Electronic could a fuel pressure sensor on the fuel rail or the fuel pump control module.

worn out piston rings require replacement..

There are few possibilities that can cause such problem.
I recommend you few help links related to your problem.Click the link below and follow the troubleshooting;-----Idles rough and quits when gas pedal is pressed less? http://technoanswers.blogspot.in/2012/01/1999-ford-f-150-idles-rough-and-quits.html-----------
Brake pedal stuck? http://howtobyme.blogspot.in/2012/03/brake-pedal-stuck.html

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Car only starts when gas pedal is pressed? http://technoanswers.blogspot.com/2012/01/car-only-starts-when-gas-pedal-is.html

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Car won't start without hitting the gas pedal? http://schematicsdiagram.blogspot.com/2011/12/car-wont-start-without-hitting-gas.html

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emits whitish bluish smoke and bad fuel smell from exhaust

http://schematicsdiagram.blogspot.com/2011/12/van-emits-whitish-bluish-smoke-and-bad.html

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White smoke and Acrid Smell? http://whoisbyme.blogspot.in/2012/07/white-smoke-and-acrid-smell.html
---------- Car stalls and throws white smoke from exhaust? http://repairhelpcenter.blogspot.com/2012/01/car-stalls-and-throws-white-smoke-from.html

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This will help.
Thanks.

Sorry but this has happened to me before, you might have a blown head gasket. that is where oil and or water are getting in to the piston cylinder and causing the white smoke cause the oil and water is being burnt or boiled.take it to a shop unless you have all the right tools and knowledge to do this job. i cost me like $1500 labor and parts.

check the compression in all cellenders you might have a blown head gasket, burning smell might be the gas in blown cillender not igniting

Try disconnecting the wire to the mass airflow sensor, and see if the symptoms change drastically. It's a three wire connector right behind the air filter box. This is what it looks like on a 97 4.2 liter v6. If the vehicle runs better, get some MAF cleaner fluid, and try cleaning it. It may need replacement, but only if the symptoms change with it disconnected.

Since you have replaced all those parts already, I would suggest checking out the egr valve. Also I was wondering how the coilpacks or distributor are acting? Is the truck firing on all cylinders? Very possible you have leaky injector also.

Hello chris first thing you need to do is while the car is running go to the rear of your car have somone increase the gas pedal to get it to smoke now smell the smoke does it smell like antifreeze if it does most likely headgasket going wich means your head needs to be pulled to change the gasket if it smells like oil possible valve seals clogged oil returns this is all serviced under your valve cover if car is turbo turbo seal internal most likely ruptured and is letting oil get into the exhaust port side have your turbo checked if there is wettness around the housing areallook for exsesive oil leaking externally goodluck please rate