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It is not likely for bad ignition coils. These are igniter malfunction codes. The computer does not see IGT or IGF. There are four separate IGT inputs from the computer to each individual ignition coil. There is only one IGF input wire back to the computer. Normally what you find is one of the ignition coils is shorting out IGF and it kills all four signals to all for coils. Or it could be intermittent and only allowing two or more coils to fire. Normally if you get one of the four codes that consistently sets first or by itself that is the suspected coil. Look at the tops of the coil to see if there any cracks or de-formations a lot of times it will be to be deformed and have a crack in the top. Check your wiring harness also to make sure there is no rodent damage to the wires running along the top of the valve cover.