2003 chevy Malibu...drives fine, park it in a parking lot, come out and it wont start. It will turn over but no start. The next day It will start and run fine for a month and again it not start for t

https://www.chevymalibuforum.com/forums/60-problems-service-issues-troubleshooting-generations-5-6/3650-04-malibu-maxx-sudden-hard-shift.html

yeah my problem is the same the shifter has to sometimes be imunipulated to assure its in park or the ignition will not turn all the way off leaving a weak or dead battery the following day. i would play with the shifter to be sure its in park all the way

have you checked the timing belt?? this would cause there to be no compression it may also have bent some valves

did you check the fluid in the transmissin it could be low or also it could need a new transmission filter i wouldnt try to drive it it anymore without checkin or changin it because it will burn it up

Antitheft system?

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timing chain could have jumped timing if you hear timing chain noise.

is the car fully in park if it is then u may have a prob with the park lock. In normal operation the key wont turn off all the way if it is not in park check to see if the censor is working or engaging. If all is working correctly then it might be that the tumblers in the ignition lock cylinder are the problem

Hello, I read your problem, and a lot of the symptoms you are describing seem like itmis possible, that you have a bad 02 sensor, this is part of your emissions, relating to the cadilac converter, it mostly acts up at lower speeds, like coming to a stop or slowing to make a corner. Sometimes also a bad fuel filter could cause this when rpms are down such as slowing or on corners. That is the two things I would check. Thanks mike

Hello Vicky...
Your Malibu has what is known as a parasitic drain...It could be a stuck relay, trunk light staying on, or a direct short circuit.Something in the electrical circuit is not turning off when then ignition switch is turned off..
You will need to perform a parasitic draw test to determine the cause and correct the problem to keep the battery from draining,

Good luck...i hope this helps

maybe it is not completely in park ?? Try starting it in neutral.