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Hello, my name is***** anything been replaced yet? Thanks.
So problem is taken care of as of now?
The P0491 and 0492 are caused by a buildup of carbon in the channels in the head for the secondary air system. It requires you to bore these channels back out with an extra long drill bit of the appropriate size.
The P2181 is usually caused by a thermostat that is sticking open slightly, just enough that the engine does not warm up according to a timed map in the ECM. Often we replace the thermostat and the engine coolant temp sensor on the back of the head at the same time.
The coil issues are all on the same side- have you checked for any other wiring damage in the harness?
Have you checked the wiring to the coil pack? I don't understand how the car can be running smooth with a coil issue for 3 cylinders! Have you tried doing a capacitive discharge to make sure the codes are not just "burned" into the memory? After clearing faults, disconnect the battery, touch the cable ends together for about a minute, then reconnect. This will reset all modules