Oil pressure gauge not functioning (91’ 3FE) (1 Viewer)

[Youngypsy]

Hey guys looking for some insight on the notorious non-functional oil pressure gauge in my 80 series.

I ended up replace the oil pressure sensor and connector to it and got maybe 5 minutes of functional readings but even then it was very skewed and eventually pinned all the way to the top of the gauge. Wire to the connector had good voltage reading so I'm thinking the wiring is fine but did read in other threads of some people ended up replacing that wire due to the constant heat it gets exposed to.

Ultimately, i plan to replace the gauge but wanted to see if anyone else had encountered this issue and it wasn’t necessarily a bad gauge but potentially something else like the wire or relay by chance before dropping $100 to potentially mess up a new gauge.

when hooking up a aftermarket gauge to read pressure idle is at 30-35psi so too all good there!

Thanks!

 

[jonheld]

The oil pressure sender is a variable resistor to ground. The gauge gets +12 from the GAUGE fuse and the sender varies the resistance. Lowest reading of the gauge is no ground path.
If the gauge is pinned to the top, it's a short to ground.
Troubleshooting is on page BE-38 of the FSM.

 

[Youngypsy]

finally decided to dive back into this project this weekend ( stereo install so figured I’d dive into this as well since the trim pieces would be off ) and wanted to rule out if my gauge was no good or simply just a wiring/ ground mishap. Turns out the gauge itself shorted and got super hot resulting in major discoloration and even melted plastic (explains why the gauge was unresponsive) so a new gauge will have to be in order.

As far as troubleshooting should I start with continuity testing? I also have some concerns with how the connection is established to the sender gauge, does this look normal or potentially something missing? Any reference photos of you guys with a 3FE would be killer!!

 

[Youngypsy]

Going to dive into my FSM tonight, looks like my digital version stopped working so apologies if anything is redundant!

 

[Funner]

My journey.

Thread 'Dead oil pressure gauge- Fixed'

Sep 26, 2015

I do have oil pressure, but gauge is dead, indicator is sitting just below L.

I first threw some money at it thinking it was highly probable that the sender died just shy of 250K miles. Installed new sender and no go, same issue as before -gauge below L.

Checked wiring over and found some suspect PO splices. Pulled the harness for the AC switch and sender. tested continuity and even though it checked out I went ahead and cleaned up the crap wiring hack and put things back together.

Pulled out FSM and suspect the receiver gauge in the dash may be my problem. There is a test for this...

• Funner
• Replies: 17
• Forum: 80-Series Tech