Reset the codes on the machine ( it instructs the ECU to reset them ) and see how many come back as some may be induced as you tinkered with the systems .

 

P0727 - Engine Speed Input Circuit No Signal

P0700 series code are specific transmission codes that your reader can see

Possible causes

Faulty Crankshaft Position (CKP) Sensor

Crankshaft Position (CKP) Sensor harness is open or shorted

Crankshaft Position (CKP) Sensor circuit poor electrical connection Communication error
between the Engine Control Module (ECM) and Transmission Control Module (TCM)
( that transmission connector we talked about cleaning maybe but you have more
symptoms of a bad sensor or a dirty sensor ( not transmission ) connector itself as
the engine stalls just after the start sequence that may or may not be related to
it's communication to the TCM as you shift )

The cheap try is to clean the Crankshaft position sensor . The wire goes back over the top of the engine so look for damaged insulation . From what I've read it's not a bad idea to keep a spare sensor in the trunk if you have the money

Read more: https://www.autocodes.com/p0727.html

 

Thank you I'll go out and check on that now.