P1258 GMC -

Question

engine rotates but will not start, also have P0300, change wires and Spark plugs

Answer 1

Hi there,

This code, P1258 is for an over temp condition. It could be the result of the coolant temp sensor or some other issue. I would check and make sure the coolant level is full and there is spark when cranking the engine.
P1258 GMC - Engine Coolant Overtemperature Protection Mode Active

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