Car shudders and dies?

In most of cases this is caused by dirt throttle plate.Carbon build up on throttle plate.Get the throttle body cleaned completely,with throttle clearer, which you can get from local auto parts store.But if that is not helping,then I believe your concern is the transaxle. I believe your losing line pressure from internal leaks in the transaxle and this is causing the converter clutch to engage. You need to have the line pressure monitored as well as the converter clutch using a pressure gauge and scan tool.Either get this test done at professional auto garage or at dealership or get this tools from local auto parts store, to perform the test yourself.At auto parts store, they provide the pressure gauge tool and scan tool for rent and when you return the tools back, they deduct there minimum fees and return you the remaining amount.

This details will help you to test and confirm the problem.

Car stays running even after key is removed?

Car will not turn off ,the key is removed but still car is not turning off.This problem is basically related to faulty ignition switch.Its either stuck up in one position or its got faulty,so its not turning up till OFF position.Get the ignition switch checked inspected,this will will help to take care of this problem.
If possible always buy car parts from proper dealer instead of local aftermarket car parts store. Original OEM parts are costly, but they last long and always supports your vehicle.

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For more car related problem troubleshooting:---

This are the sections, you can go through and click the link to read its troubleshooting.

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The car will not start?

http://schematicsdiagram.blogspot.com/2011/06/car-will-not-start.html

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Car will not crank?

http://schematicsdiagram.blogspot.com/2011/06/car-will-not-crank.html

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Car has no spark?

http://schematicsdiagram.blogspot.com/2011/06/car-has-no-spark.html

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How to troubleshoot car battery?

http://schematicsdiagram.blogspot.com/2011/06/how-to-troubleshoot-car-battery.html

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How to test starter solenoid?

http://schematicsdiagram.blogspot.com/2011/06/how-to-test-starter-solenoid.html

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How to test cars starter?

http://schematicsdiagram.blogspot.com/2011/06/how-to-test-cars-starter.html

How to replace starter in car?

http://schematicsdiagram.blogspot.com/2011/06/how-to-replace-starter-in-car.html

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car will turn over but will not start?

http://technoanswers.blogspot.com/2011/05/car-will-turn-over-but-will-not-start.html

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Car wont start?

http://howtobyme.blogspot.com/2011/10/car-wont-start.html

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