Oil Pressure guage vs Sender unit

I have a 92' 400e, 102K miles, and the oil pressure gauge fluctuates like crazy... Previously (lower miles) it hung pretty steady a 3...except for idle,
then down to between 1 and 2. Now it jumps all over, when the RPM changes... at hgwy speeds (3k RPM) it stays pretty steady at 3, but when in traffic it drops to 0 ... then when accelerating to about 2K rpm.. it will jump to 1 maybe 2 on the oil pressure gauge... then drop dramatically (to zero) when RMP drops below 2K or 1.5 K , way too erratic for me.. I am concerned that when i am slow traffic and the gauge is at zero, that the oil pump is truely at fault and i am causing harm, or is it possibly a faulty gauge, and the engine pump is actually fine, thereby false readings.... shoudl i be concerned about the oil pump?? thnaks.. Mike
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
At 102K miles it's very unlikely that the engine's oil pressure is low or erratic. Erratic gauge is most likely an electrical issue - poor connection, poor ground connection, faulty sender or gauge itself.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I had the same problem last year also in a 1992 400e which at the time had around 95000 miles. The pressure gauge would jump around, usually at idle and you could sometimes hear it clicking at the high and low range. The dealer replaced the pressure sending unit, and now it indicates 3 all the time, even at idle.
Rob

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Thet all puts me in mind of tha time mah neibor in tha nex trailer fixed his problem like thet. He painted a needle on the dial at 3 and it wus fixed!!!!!
mcbrue under the bridge in the trailer down by the river
96 S420
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.