The codes are telling you something is wrong with the transmission controls. P0717 is the main culprit for harsh and erratic shifting.
I don't think flushing the system is the solution to his. You need to check out the circuit. I told you to check the connectors and have you done them? You need to do as advised to get to the bottom of the problem and that requires testing and diagbnostics.
If external testings cannot find any fault, the problem would be internal and that would require stripping the trans to rebuild etc.
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Sunday, August 26th, 2012 AT 1:46 PM