Battery went dead check engine light warned me.then code p1621 How do I fix this.

Question

Have been having problems clearing evap code after replacing vent control when it failed do to a smoke test.

Answer 1

HI there,

This code is for the computer long term memory performance.

With this code it's basically calling to have the computer programmed, if it is attempted twice and it fails, then replace the PCM and reprogram the new one.