P0306 2006 Toyota Highlander - would this cause delay in automatic gear selection

Question

P0306 TOYOTA HIGHLANDER 2006- I observed that after the car has selected from gear 2, it delays and makes heavy noise before moving to gear 3. Sometimes it does not change gear.

Answer 1

P0306 is a misfire code unless the car is in fail safe move it is not related to slow shifting or noise. 

start by replacing the spark plugs if you have not done so. 

if the code comes back swap the ignition coil from cylinder 4 to 6 and see if the code moves to cylinder 4 if it does replace the ignition coil.

 

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