Q: Misfire codes

asked by on June 09, 2017

I was driving my car I turned on the heater and now it won't run good when I hook up the scanner it I get codes p0300 p0304 p0305 p0306 good fuel pressure no leaks good ignition coils good compression on all cylinders I changed spark plugs ignition coils check for leaks what could it be a bad coolant temp sensor?

My car has 140000 miles.
My car has an automatic transmission.

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