Question

2007 toyota  avalon, l can't get rid of p0351 code ,replace  the coil and knock sensor, reset check  engine light  then comes  back  on as  soon  as  I turn  the  ignition  switch  on ?

Answer 1

P0351 Ignition coil "A" primary / secondary circuit

P0351 is dealing with No. 1 ignition coil circuit., rule out the secondary ignition , inspect the sparkplug wire and if any dielectric grease on the sparkplug remove it  and retest. , The worse this code related to is with the ECM.