Anyone here know how to test the Oil Pressure Sending Unit to see if it is bad? I have an '04 SE CC with 93,500 miles on it and the Oil Pressure Gauge has recently started acting weird. It will peg out on H when the truck first cranks and will only return to the middle (normal operating range for the first 93,000 mile) when I come to a complete stop. I've searched other posts on the forum and I can't find a spec on how to check the sending unit with a multimeter. Any help from you pros would be appreciated. Thanks.
That is correct Helomech. That is the part that worries me. It has never stayed this high before. Normal operating range for my Titan was just above the middle mark after the engine had warmed up. The pressure would increase at times depending on RPM's however this was minimal and in my mind to be expected. I ran the gauge diagnostics to check the gauges and they all seem to be working properly. Oil level is also perfect. I even changed out the oil filter thinking this might have an effect but nothing changed.
The service manual says to remove engine front undercover (not sure what that means). Then remove oil pressure sensor. They show a regular looking pressure gauge with a flexible hose on it. You hook the pressure gauge to the spot where the pressure sensor was. In the pic it looks like it is right above and to the rear of the oil filter, but the pic isn't that good. Idle speed pressure should be 14psi, and at 2000 rpm pressure should be 43 psi with a warmed up engine and running under no load.
Thanks Helomech. I don't have a pressure gauge available but I will try to pick one up and get back with the results. I think the engine front undercover is the metal splash guard you have to remove to get to the oil filter. If anyone else comes up with an electrical test I would appreciate a response. Love this forum!
The manual doesn't say what size the threads are for the sending unit. I guess you could pull it out in the parking lot of the store. The sending unit is above the oil pan, so you should not loose much oil.