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Is the check engine light on while driving?
Even if the remote start is the source of the problem, the trouble codes will still be in the computer for 40 drive cycles or until the codes are cleared with a scan tool. If you can get the codes scanned and then cleared this may alleviate the problem. Record what number the trouble code is and let me know if you need additional help.
I believe the problem is in the torque converter clutch system. When there is slippage, the P0894 code will set.
Action Taken When the P0894 DTC Sets
Below is a list of potential problems that can cause the P0894 code.