4-1-3 If that is "EGR flow too low", then you should experience no performance issues, but you may experience not passing smog. The EGR directly lowers NOx emissions.

The wire connector is about 8-16 inches back from the sensor. SOP is to remove the valve, sensor, and tube between the exhaust and EGR valve, and the tube between EGR valve and intake manifold. Loosen the tube's big 19mm(?) nuts before loosening the EGR mounting bolts.

The most likely candidate is that the smaller tube to the intake from the valve is blocked, the solenoid is not working, or the sensor is failed.

There are two versions of the sensor - one is NTC, one is PTC - and they have both different threading and different locations. I don't recall which is which, but I think it's in the FAQ. You should just match whatever one you have, if you have one.

You can test its resistance (it should not read 0 or infinite) at two different temperatures. The value changing indicates a sensor that works at least somewhat, if the value does not change, the sensor's toast. Usually you will see an open (infinite resistance) failure.

Note that the EGR mounting bolts are the same bolts that mount the oil breather box, and now is a good time to replace the breather box with OE. The Aftermarket ones don't hold up (personally verified). It makes it easier to remove the EGR/breather if you remove the intake and/or throttle body, but it's not necessary.

You may want to soak the EGR pipe nuts with WD-40 (or PB Blaster) for a few days and run the engine on those days.

Good Luck!