Car will start but when you go to take off car dies

hi David.
you have not give make or model.
but try this link might help you out.
Car starts then dies Google Search

Crankshaft sensor.

sounds like a fuel filter issue is there an inline filter

It could be the filter, but it could also be the fuel pump.

ECU ?

You have a fusable link under the hood this is what i find for Saturn

It can be issue with fuel pressure,its low or the problem relates to faulty spark plugs.
There are few troubleshooting steps to confirm the problem.I suggest you few help links,with complete troubleshooting and solution for these types of issues.

1991 Toyota Trecel: Engine Starts fine but dies when gets Warm? http://whatisbyme.blogspot.in/2012/05/1991-toyota-trecel-engine-starts-fine.html

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1994 Toyota Pickup: Starts fine but dies in few seconds?

http://howtobyme.blogspot.in/2012/05/1994-toyota-pickup-starts-fine-but-dies.html

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1994 Lexus ES300: Engine Idles Rough and Dies? http://whatisbyme.blogspot.in/2012/05/1994-lexus-es300-engine-idles-rough-and.html

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Stalls And Dies At Stop Sign? http://www.howtobyme.blogspot.com/2012/07/stalls-and-dies-at-stop-sign.html

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Car dies when gas pedal is pressed? http://schematicsdiagram.blogspot.com/2011/12/car-dies-when-gas-pedal-is-pressed.html

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These help links will help you to troubleshoot and solve the issue.
Thanks.

Your fuel pump is probally shot.

replace the crank shaft position sensor the cam sensor will make hard starting not no starting in most cases

try checking the thermostat control senser. it caused my bronco to start for a second and then die. after a while it would finally start and run for a while then die driving down the road. i changed the thermostat control senser and it fixed all problems of dieing