Weird. My Oil Pressure Sensor Sender Switch failed the day I picked up my 04 from my mechanic in March. The 04 had several oil leaks haunting my driveway. My mechanic successfully repaired them all. Took the 04 in yesterday for an oil change at Walmart. They refused to change it when their tech noticed the HI pressure indication. Looks as if I am in the market for a new Oil Pressure Sensor Sender Switch. Below are some links I have found after reading this thread.
You will need a 15/16 wrench and a bucket for the coolant, there was a hose in the way. I could have clamped it but I had the new coolant and needed to replace it anyways. I replaced the oil and the filter at the same time so there was no filter in the way possibly allowing more knuckle space.
A pleasant surprise after the oil was added....... Gauge pointing up. Yay