P1899 fault code on 2000 Plymouth Neon

I got a p1899 fault code during my smog test. The engine fault light is on but goes out when i fill the gas tank or apply any heavy load on the car or when the gas tank is almost empty. Any suggestions on how to fix the park/neutral switch

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1 answer
This code seems to be related to the park/neutral safety switch, so that will need to be checked out. Probably needs to be replaced or adjusted.
I would get a good repair manual to learn how to troubleshoot this or take it to a shop and have it done for you.
http://bit.ly/mitchell_repair_manuals_online
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