did I get the wrong oil pres. sending unit?

[discobayexplore]

Thanks in advance for the info.
I have a 94 XLT 4.0 v-6. I was getting erratic readings from my oil pressure gauge (mostly fine but now and then would swing low). Everything seemed fine so I thought it might be the sending unit acting up...and it is an easy 10 buck fix......but....now I notice that the needle does not move AT ALL (after starting that is.....goes straight to middle of the gauge and stays there when its running)..I get smack dab in the middle of normal...at idle...and under a load. Shouldn't the gauge be moving back and forth at least a little? did the parts guy give me an idiot light sending unit? can this be right? every car I have ever had with an oil pressure gauge moves at least a little when you goose it........
Thanks!

 

[Maniak]

There was a long thread about oil pressure sending units a long time ago.. I think it was something like "fake oil guage" etc.. The Oil pressure sending unit is really just a switch.. over 5psi it shows good.. under 5psi it shows low.. You can buy a regular oil pressure sending unit.... The easiest way for me to get it was to tell them I had a 1973 Ford E-150 with a 300 inline 6 motor.. The fitting is the same size and the wire connected to it no problem. Once you put in that now sender you pressure guage will be more than an analog idiot light. It will read slow/low but that is an easy fix. If you pull the guage cluster out you will see 2 big resisters. One is marked 200ohm and the other was marked something much higher (written right on the printed circuit board). All you have to do is short out the 200 ohm resister (I just soldered a wire over it incase I needed to ever go back).. Now our guage works correctly..

High idle in the morning shows high.. Once the motor/oil warms up the oil pressure is 1/3 way up at idle and reacts normally when I bring up the rpms.. It is nice having a real pressure gauge.

Here are 3 part numbers for the correct sending unit (real sending unit one.. not analog idiot light one)..
My Neihoff box had the following part numbers on the top..
GEN: OP24761
NEI: FF133E
SMP: PS-60

Mark