I have a 2004 320 with 8.1s. Last Friday, the Port engine would not run over 3000 RPM and I could smell unburned fuel. I changed the plugs and she ran like a top, up to about 4400 RPM, but mostly about 3400 rpm for about 10 minutes. The computer then told me I had no water pressure on the port engine. It was a bit warmer than the starboard engine but not excessively hot, 161 degrees port vs 147 starboard. I could have coincidentally trashed an impeller but is it possible I knocked the water pressure sensor loose? Can anybody tell me where to look for the sensor and what it Looks Like? I would like to trade the sensor from the starboard engine to the port engine if it is reasonable to do so. Thoughts?