Diagnostics by simply unplugging sensors can work, BUT unless you know exactly what the response should be and can see the actual changes the computer makes on either a scan tool or a scope it isn't something that will really help. Also it will set other codes. As the good Doctor pointed out, those codes are a road map to the problem. If you unplug items at random the map gets very confusing.
Could it be something like a fuse, plugs or fluids? Yes, however that is only because of the result from those items.
The fuse could be blown and that causes the system it powers (say the EVAP purge valve) to fail when the computer tells it to open, that failure triggers the light.
Bad plugs could cause a misfire, that would trigger the light.
In the case of fluids, it would depend on the fluid, low oil or coolant in themselves won't trigger a light, but low oil pressure or high coolant temperatures could depending on what else they effect.
This is why the best first step is a simple code scan.
Wednesday, April 19th, 2017 AT 7:42 AM